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This is libc.info, produced by makeinfo version 5.2 from libc.texinfo.
This file documents the GNU C Library.
This is 'The GNU C Library Reference Manual', for version 2.19
(Buildroot).
Copyright (C) 1993-2014 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with the
Invariant Sections being "Free Software Needs Free Documentation" and
"GNU Lesser General Public License", the Front-Cover texts being "A GNU
Manual", and with the Back-Cover Texts as in (a) below. A copy of the
license is included in the section entitled "GNU Free Documentation
License".
(a) The FSF's Back-Cover Text is: "You have the freedom to copy and
modify this GNU manual. Buying copies from the FSF supports it in
developing GNU and promoting software freedom."
INFO-DIR-SECTION Software libraries
START-INFO-DIR-ENTRY
* Libc: (libc). C library.
END-INFO-DIR-ENTRY
INFO-DIR-SECTION GNU C library functions and macros
START-INFO-DIR-ENTRY
* ALTWERASE: (libc)Local Modes.
* ARGP_ERR_UNKNOWN: (libc)Argp Parser Functions.
* ARG_MAX: (libc)General Limits.
* BC_BASE_MAX: (libc)Utility Limits.
* BC_DIM_MAX: (libc)Utility Limits.
* BC_SCALE_MAX: (libc)Utility Limits.
* BC_STRING_MAX: (libc)Utility Limits.
* BRKINT: (libc)Input Modes.
* BUFSIZ: (libc)Controlling Buffering.
* CCTS_OFLOW: (libc)Control Modes.
* CHILD_MAX: (libc)General Limits.
* CIGNORE: (libc)Control Modes.
* CLK_TCK: (libc)Processor Time.
* CLOCAL: (libc)Control Modes.
* CLOCKS_PER_SEC: (libc)CPU Time.
* COLL_WEIGHTS_MAX: (libc)Utility Limits.
* CPU_CLR: (libc)CPU Affinity.
* CPU_ISSET: (libc)CPU Affinity.
* CPU_SET: (libc)CPU Affinity.
* CPU_SETSIZE: (libc)CPU Affinity.
* CPU_ZERO: (libc)CPU Affinity.
* CREAD: (libc)Control Modes.
* CRTS_IFLOW: (libc)Control Modes.
* CS5: (libc)Control Modes.
* CS6: (libc)Control Modes.
* CS7: (libc)Control Modes.
* CS8: (libc)Control Modes.
* CSIZE: (libc)Control Modes.
* CSTOPB: (libc)Control Modes.
* DES_FAILED: (libc)DES Encryption.
* DTTOIF: (libc)Directory Entries.
* E2BIG: (libc)Error Codes.
* EACCES: (libc)Error Codes.
* EADDRINUSE: (libc)Error Codes.
* EADDRNOTAVAIL: (libc)Error Codes.
* EADV: (libc)Error Codes.
* EAFNOSUPPORT: (libc)Error Codes.
* EAGAIN: (libc)Error Codes.
* EALREADY: (libc)Error Codes.
* EAUTH: (libc)Error Codes.
* EBACKGROUND: (libc)Error Codes.
* EBADE: (libc)Error Codes.
* EBADF: (libc)Error Codes.
* EBADFD: (libc)Error Codes.
* EBADMSG: (libc)Error Codes.
* EBADR: (libc)Error Codes.
* EBADRPC: (libc)Error Codes.
* EBADRQC: (libc)Error Codes.
* EBADSLT: (libc)Error Codes.
* EBFONT: (libc)Error Codes.
* EBUSY: (libc)Error Codes.
* ECANCELED: (libc)Error Codes.
* ECHILD: (libc)Error Codes.
* ECHO: (libc)Local Modes.
* ECHOCTL: (libc)Local Modes.
* ECHOE: (libc)Local Modes.
* ECHOK: (libc)Local Modes.
* ECHOKE: (libc)Local Modes.
* ECHONL: (libc)Local Modes.
* ECHOPRT: (libc)Local Modes.
* ECHRNG: (libc)Error Codes.
* ECOMM: (libc)Error Codes.
* ECONNABORTED: (libc)Error Codes.
* ECONNREFUSED: (libc)Error Codes.
* ECONNRESET: (libc)Error Codes.
* ED: (libc)Error Codes.
* EDEADLK: (libc)Error Codes.
* EDEADLOCK: (libc)Error Codes.
* EDESTADDRREQ: (libc)Error Codes.
* EDIED: (libc)Error Codes.
* EDOM: (libc)Error Codes.
* EDOTDOT: (libc)Error Codes.
* EDQUOT: (libc)Error Codes.
* EEXIST: (libc)Error Codes.
* EFAULT: (libc)Error Codes.
* EFBIG: (libc)Error Codes.
* EFTYPE: (libc)Error Codes.
* EGRATUITOUS: (libc)Error Codes.
* EGREGIOUS: (libc)Error Codes.
* EHOSTDOWN: (libc)Error Codes.
* EHOSTUNREACH: (libc)Error Codes.
* EHWPOISON: (libc)Error Codes.
* EIDRM: (libc)Error Codes.
* EIEIO: (libc)Error Codes.
* EILSEQ: (libc)Error Codes.
* EINPROGRESS: (libc)Error Codes.
* EINTR: (libc)Error Codes.
* EINVAL: (libc)Error Codes.
* EIO: (libc)Error Codes.
* EISCONN: (libc)Error Codes.
* EISDIR: (libc)Error Codes.
* EISNAM: (libc)Error Codes.
* EKEYEXPIRED: (libc)Error Codes.
* EKEYREJECTED: (libc)Error Codes.
* EKEYREVOKED: (libc)Error Codes.
* EL2HLT: (libc)Error Codes.
* EL2NSYNC: (libc)Error Codes.
* EL3HLT: (libc)Error Codes.
* EL3RST: (libc)Error Codes.
* ELIBACC: (libc)Error Codes.
* ELIBBAD: (libc)Error Codes.
* ELIBEXEC: (libc)Error Codes.
* ELIBMAX: (libc)Error Codes.
* ELIBSCN: (libc)Error Codes.
* ELNRNG: (libc)Error Codes.
* ELOOP: (libc)Error Codes.
* EMEDIUMTYPE: (libc)Error Codes.
* EMFILE: (libc)Error Codes.
* EMLINK: (libc)Error Codes.
* EMSGSIZE: (libc)Error Codes.
* EMULTIHOP: (libc)Error Codes.
* ENAMETOOLONG: (libc)Error Codes.
* ENAVAIL: (libc)Error Codes.
* ENEEDAUTH: (libc)Error Codes.
* ENETDOWN: (libc)Error Codes.
* ENETRESET: (libc)Error Codes.
* ENETUNREACH: (libc)Error Codes.
* ENFILE: (libc)Error Codes.
* ENOANO: (libc)Error Codes.
* ENOBUFS: (libc)Error Codes.
* ENOCSI: (libc)Error Codes.
* ENODATA: (libc)Error Codes.
* ENODEV: (libc)Error Codes.
* ENOENT: (libc)Error Codes.
* ENOEXEC: (libc)Error Codes.
* ENOKEY: (libc)Error Codes.
* ENOLCK: (libc)Error Codes.
* ENOLINK: (libc)Error Codes.
* ENOMEDIUM: (libc)Error Codes.
* ENOMEM: (libc)Error Codes.
* ENOMSG: (libc)Error Codes.
* ENONET: (libc)Error Codes.
* ENOPKG: (libc)Error Codes.
* ENOPROTOOPT: (libc)Error Codes.
* ENOSPC: (libc)Error Codes.
* ENOSR: (libc)Error Codes.
* ENOSTR: (libc)Error Codes.
* ENOSYS: (libc)Error Codes.
* ENOTBLK: (libc)Error Codes.
* ENOTCONN: (libc)Error Codes.
* ENOTDIR: (libc)Error Codes.
* ENOTEMPTY: (libc)Error Codes.
* ENOTNAM: (libc)Error Codes.
* ENOTRECOVERABLE: (libc)Error Codes.
* ENOTSOCK: (libc)Error Codes.
* ENOTSUP: (libc)Error Codes.
* ENOTTY: (libc)Error Codes.
* ENOTUNIQ: (libc)Error Codes.
* ENXIO: (libc)Error Codes.
* EOF: (libc)EOF and Errors.
* EOPNOTSUPP: (libc)Error Codes.
* EOVERFLOW: (libc)Error Codes.
* EOWNERDEAD: (libc)Error Codes.
* EPERM: (libc)Error Codes.
* EPFNOSUPPORT: (libc)Error Codes.
* EPIPE: (libc)Error Codes.
* EPROCLIM: (libc)Error Codes.
* EPROCUNAVAIL: (libc)Error Codes.
* EPROGMISMATCH: (libc)Error Codes.
* EPROGUNAVAIL: (libc)Error Codes.
* EPROTO: (libc)Error Codes.
* EPROTONOSUPPORT: (libc)Error Codes.
* EPROTOTYPE: (libc)Error Codes.
* EQUIV_CLASS_MAX: (libc)Utility Limits.
* ERANGE: (libc)Error Codes.
* EREMCHG: (libc)Error Codes.
* EREMOTE: (libc)Error Codes.
* EREMOTEIO: (libc)Error Codes.
* ERESTART: (libc)Error Codes.
* ERFKILL: (libc)Error Codes.
* EROFS: (libc)Error Codes.
* ERPCMISMATCH: (libc)Error Codes.
* ESHUTDOWN: (libc)Error Codes.
* ESOCKTNOSUPPORT: (libc)Error Codes.
* ESPIPE: (libc)Error Codes.
* ESRCH: (libc)Error Codes.
* ESRMNT: (libc)Error Codes.
* ESTALE: (libc)Error Codes.
* ESTRPIPE: (libc)Error Codes.
* ETIME: (libc)Error Codes.
* ETIMEDOUT: (libc)Error Codes.
* ETOOMANYREFS: (libc)Error Codes.
* ETXTBSY: (libc)Error Codes.
* EUCLEAN: (libc)Error Codes.
* EUNATCH: (libc)Error Codes.
* EUSERS: (libc)Error Codes.
* EWOULDBLOCK: (libc)Error Codes.
* EXDEV: (libc)Error Codes.
* EXFULL: (libc)Error Codes.
* EXIT_FAILURE: (libc)Exit Status.
* EXIT_SUCCESS: (libc)Exit Status.
* EXPR_NEST_MAX: (libc)Utility Limits.
* FD_CLOEXEC: (libc)Descriptor Flags.
* FD_CLR: (libc)Waiting for I/O.
* FD_ISSET: (libc)Waiting for I/O.
* FD_SET: (libc)Waiting for I/O.
* FD_SETSIZE: (libc)Waiting for I/O.
* FD_ZERO: (libc)Waiting for I/O.
* FILENAME_MAX: (libc)Limits for Files.
* FLUSHO: (libc)Local Modes.
* FOPEN_MAX: (libc)Opening Streams.
* FP_ILOGB0: (libc)Exponents and Logarithms.
* FP_ILOGBNAN: (libc)Exponents and Logarithms.
* F_DUPFD: (libc)Duplicating Descriptors.
* F_GETFD: (libc)Descriptor Flags.
* F_GETFL: (libc)Getting File Status Flags.
* F_GETLK: (libc)File Locks.
* F_GETOWN: (libc)Interrupt Input.
* F_OK: (libc)Testing File Access.
* F_SETFD: (libc)Descriptor Flags.
* F_SETFL: (libc)Getting File Status Flags.
* F_SETLK: (libc)File Locks.
* F_SETLKW: (libc)File Locks.
* F_SETOWN: (libc)Interrupt Input.
* HUGE_VAL: (libc)Math Error Reporting.
* HUGE_VALF: (libc)Math Error Reporting.
* HUGE_VALL: (libc)Math Error Reporting.
* HUPCL: (libc)Control Modes.
* I: (libc)Complex Numbers.
* ICANON: (libc)Local Modes.
* ICRNL: (libc)Input Modes.
* IEXTEN: (libc)Local Modes.
* IFNAMSIZ: (libc)Interface Naming.
* IFTODT: (libc)Directory Entries.
* IGNBRK: (libc)Input Modes.
* IGNCR: (libc)Input Modes.
* IGNPAR: (libc)Input Modes.
* IMAXBEL: (libc)Input Modes.
* INADDR_ANY: (libc)Host Address Data Type.
* INADDR_BROADCAST: (libc)Host Address Data Type.
* INADDR_LOOPBACK: (libc)Host Address Data Type.
* INADDR_NONE: (libc)Host Address Data Type.
* INFINITY: (libc)Infinity and NaN.
* INLCR: (libc)Input Modes.
* INPCK: (libc)Input Modes.
* IPPORT_RESERVED: (libc)Ports.
* IPPORT_USERRESERVED: (libc)Ports.
* ISIG: (libc)Local Modes.
* ISTRIP: (libc)Input Modes.
* IXANY: (libc)Input Modes.
* IXOFF: (libc)Input Modes.
* IXON: (libc)Input Modes.
* LINE_MAX: (libc)Utility Limits.
* LINK_MAX: (libc)Limits for Files.
* L_ctermid: (libc)Identifying the Terminal.
* L_cuserid: (libc)Who Logged In.
* L_tmpnam: (libc)Temporary Files.
* MAXNAMLEN: (libc)Limits for Files.
* MAXSYMLINKS: (libc)Symbolic Links.
* MAX_CANON: (libc)Limits for Files.
* MAX_INPUT: (libc)Limits for Files.
* MB_CUR_MAX: (libc)Selecting the Conversion.
* MB_LEN_MAX: (libc)Selecting the Conversion.
* MDMBUF: (libc)Control Modes.
* MSG_DONTROUTE: (libc)Socket Data Options.
* MSG_OOB: (libc)Socket Data Options.
* MSG_PEEK: (libc)Socket Data Options.
* NAME_MAX: (libc)Limits for Files.
* NAN: (libc)Infinity and NaN.
* NCCS: (libc)Mode Data Types.
* NGROUPS_MAX: (libc)General Limits.
* NOFLSH: (libc)Local Modes.
* NOKERNINFO: (libc)Local Modes.
* NSIG: (libc)Standard Signals.
* NULL: (libc)Null Pointer Constant.
* ONLCR: (libc)Output Modes.
* ONOEOT: (libc)Output Modes.
* OPEN_MAX: (libc)General Limits.
* OPOST: (libc)Output Modes.
* OXTABS: (libc)Output Modes.
* O_ACCMODE: (libc)Access Modes.
* O_APPEND: (libc)Operating Modes.
* O_ASYNC: (libc)Operating Modes.
* O_CREAT: (libc)Open-time Flags.
* O_EXCL: (libc)Open-time Flags.
* O_EXEC: (libc)Access Modes.
* O_EXLOCK: (libc)Open-time Flags.
* O_FSYNC: (libc)Operating Modes.
* O_IGNORE_CTTY: (libc)Open-time Flags.
* O_NDELAY: (libc)Operating Modes.
* O_NOATIME: (libc)Operating Modes.
* O_NOCTTY: (libc)Open-time Flags.
* O_NOLINK: (libc)Open-time Flags.
* O_NONBLOCK: (libc)Open-time Flags.
* O_NONBLOCK: (libc)Operating Modes.
* O_NOTRANS: (libc)Open-time Flags.
* O_RDONLY: (libc)Access Modes.
* O_RDWR: (libc)Access Modes.
* O_READ: (libc)Access Modes.
* O_SHLOCK: (libc)Open-time Flags.
* O_SYNC: (libc)Operating Modes.
* O_TRUNC: (libc)Open-time Flags.
* O_WRITE: (libc)Access Modes.
* O_WRONLY: (libc)Access Modes.
* PARENB: (libc)Control Modes.
* PARMRK: (libc)Input Modes.
* PARODD: (libc)Control Modes.
* PATH_MAX: (libc)Limits for Files.
* PA_FLAG_MASK: (libc)Parsing a Template String.
* PENDIN: (libc)Local Modes.
* PF_FILE: (libc)Local Namespace Details.
* PF_INET6: (libc)Internet Namespace.
* PF_INET: (libc)Internet Namespace.
* PF_LOCAL: (libc)Local Namespace Details.
* PF_UNIX: (libc)Local Namespace Details.
* PIPE_BUF: (libc)Limits for Files.
* P_tmpdir: (libc)Temporary Files.
* RAND_MAX: (libc)ISO Random.
* RE_DUP_MAX: (libc)General Limits.
* RLIM_INFINITY: (libc)Limits on Resources.
* R_OK: (libc)Testing File Access.
* SA_NOCLDSTOP: (libc)Flags for Sigaction.
* SA_ONSTACK: (libc)Flags for Sigaction.
* SA_RESTART: (libc)Flags for Sigaction.
* SEEK_CUR: (libc)File Positioning.
* SEEK_END: (libc)File Positioning.
* SEEK_SET: (libc)File Positioning.
* SIGABRT: (libc)Program Error Signals.
* SIGALRM: (libc)Alarm Signals.
* SIGBUS: (libc)Program Error Signals.
* SIGCHLD: (libc)Job Control Signals.
* SIGCLD: (libc)Job Control Signals.
* SIGCONT: (libc)Job Control Signals.
* SIGEMT: (libc)Program Error Signals.
* SIGFPE: (libc)Program Error Signals.
* SIGHUP: (libc)Termination Signals.
* SIGILL: (libc)Program Error Signals.
* SIGINFO: (libc)Miscellaneous Signals.
* SIGINT: (libc)Termination Signals.
* SIGIO: (libc)Asynchronous I/O Signals.
* SIGIOT: (libc)Program Error Signals.
* SIGKILL: (libc)Termination Signals.
* SIGLOST: (libc)Operation Error Signals.
* SIGPIPE: (libc)Operation Error Signals.
* SIGPOLL: (libc)Asynchronous I/O Signals.
* SIGPROF: (libc)Alarm Signals.
* SIGQUIT: (libc)Termination Signals.
* SIGSEGV: (libc)Program Error Signals.
* SIGSTOP: (libc)Job Control Signals.
* SIGSYS: (libc)Program Error Signals.
* SIGTERM: (libc)Termination Signals.
* SIGTRAP: (libc)Program Error Signals.
* SIGTSTP: (libc)Job Control Signals.
* SIGTTIN: (libc)Job Control Signals.
* SIGTTOU: (libc)Job Control Signals.
* SIGURG: (libc)Asynchronous I/O Signals.
* SIGUSR1: (libc)Miscellaneous Signals.
* SIGUSR2: (libc)Miscellaneous Signals.
* SIGVTALRM: (libc)Alarm Signals.
* SIGWINCH: (libc)Miscellaneous Signals.
* SIGXCPU: (libc)Operation Error Signals.
* SIGXFSZ: (libc)Operation Error Signals.
* SIG_ERR: (libc)Basic Signal Handling.
* SOCK_DGRAM: (libc)Communication Styles.
* SOCK_RAW: (libc)Communication Styles.
* SOCK_RDM: (libc)Communication Styles.
* SOCK_SEQPACKET: (libc)Communication Styles.
* SOCK_STREAM: (libc)Communication Styles.
* SOL_SOCKET: (libc)Socket-Level Options.
* SSIZE_MAX: (libc)General Limits.
* STREAM_MAX: (libc)General Limits.
* SUN_LEN: (libc)Local Namespace Details.
* SV_INTERRUPT: (libc)BSD Handler.
* SV_ONSTACK: (libc)BSD Handler.
* SV_RESETHAND: (libc)BSD Handler.
* S_IFMT: (libc)Testing File Type.
* S_ISBLK: (libc)Testing File Type.
* S_ISCHR: (libc)Testing File Type.
* S_ISDIR: (libc)Testing File Type.
* S_ISFIFO: (libc)Testing File Type.
* S_ISLNK: (libc)Testing File Type.
* S_ISREG: (libc)Testing File Type.
* S_ISSOCK: (libc)Testing File Type.
* S_TYPEISMQ: (libc)Testing File Type.
* S_TYPEISSEM: (libc)Testing File Type.
* S_TYPEISSHM: (libc)Testing File Type.
* TMP_MAX: (libc)Temporary Files.
* TOSTOP: (libc)Local Modes.
* TZNAME_MAX: (libc)General Limits.
* VDISCARD: (libc)Other Special.
* VDSUSP: (libc)Signal Characters.
* VEOF: (libc)Editing Characters.
* VEOL2: (libc)Editing Characters.
* VEOL: (libc)Editing Characters.
* VERASE: (libc)Editing Characters.
* VINTR: (libc)Signal Characters.
* VKILL: (libc)Editing Characters.
* VLNEXT: (libc)Other Special.
* VMIN: (libc)Noncanonical Input.
* VQUIT: (libc)Signal Characters.
* VREPRINT: (libc)Editing Characters.
* VSTART: (libc)Start/Stop Characters.
* VSTATUS: (libc)Other Special.
* VSTOP: (libc)Start/Stop Characters.
* VSUSP: (libc)Signal Characters.
* VTIME: (libc)Noncanonical Input.
* VWERASE: (libc)Editing Characters.
* WCHAR_MAX: (libc)Extended Char Intro.
* WCHAR_MIN: (libc)Extended Char Intro.
* WCOREDUMP: (libc)Process Completion Status.
* WEOF: (libc)EOF and Errors.
* WEOF: (libc)Extended Char Intro.
* WEXITSTATUS: (libc)Process Completion Status.
* WIFEXITED: (libc)Process Completion Status.
* WIFSIGNALED: (libc)Process Completion Status.
* WIFSTOPPED: (libc)Process Completion Status.
* WSTOPSIG: (libc)Process Completion Status.
* WTERMSIG: (libc)Process Completion Status.
* W_OK: (libc)Testing File Access.
* X_OK: (libc)Testing File Access.
* _Complex_I: (libc)Complex Numbers.
* _Exit: (libc)Termination Internals.
* _IOFBF: (libc)Controlling Buffering.
* _IOLBF: (libc)Controlling Buffering.
* _IONBF: (libc)Controlling Buffering.
* _Imaginary_I: (libc)Complex Numbers.
* _PATH_UTMP: (libc)Manipulating the Database.
* _PATH_WTMP: (libc)Manipulating the Database.
* _POSIX2_C_DEV: (libc)System Options.
* _POSIX2_C_VERSION: (libc)Version Supported.
* _POSIX2_FORT_DEV: (libc)System Options.
* _POSIX2_FORT_RUN: (libc)System Options.
* _POSIX2_LOCALEDEF: (libc)System Options.
* _POSIX2_SW_DEV: (libc)System Options.
* _POSIX_CHOWN_RESTRICTED: (libc)Options for Files.
* _POSIX_JOB_CONTROL: (libc)System Options.
* _POSIX_NO_TRUNC: (libc)Options for Files.
* _POSIX_SAVED_IDS: (libc)System Options.
* _POSIX_VDISABLE: (libc)Options for Files.
* _POSIX_VERSION: (libc)Version Supported.
* __fbufsize: (libc)Controlling Buffering.
* __flbf: (libc)Controlling Buffering.
* __fpending: (libc)Controlling Buffering.
* __fpurge: (libc)Flushing Buffers.
* __freadable: (libc)Opening Streams.
* __freading: (libc)Opening Streams.
* __fsetlocking: (libc)Streams and Threads.
* __fwritable: (libc)Opening Streams.
* __fwriting: (libc)Opening Streams.
* __gconv_end_fct: (libc)glibc iconv Implementation.
* __gconv_fct: (libc)glibc iconv Implementation.
* __gconv_init_fct: (libc)glibc iconv Implementation.
* __ppc_get_timebase: (libc)PowerPC.
* __ppc_get_timebase_freq: (libc)PowerPC.
* __ppc_mdoio: (libc)PowerPC.
* __ppc_mdoom: (libc)PowerPC.
* __ppc_set_ppr_low: (libc)PowerPC.
* __ppc_set_ppr_med: (libc)PowerPC.
* __ppc_set_ppr_med_low: (libc)PowerPC.
* __ppc_yield: (libc)PowerPC.
* __va_copy: (libc)Argument Macros.
* _exit: (libc)Termination Internals.
* _flushlbf: (libc)Flushing Buffers.
* _tolower: (libc)Case Conversion.
* _toupper: (libc)Case Conversion.
* a64l: (libc)Encode Binary Data.
* abort: (libc)Aborting a Program.
* abs: (libc)Absolute Value.
* accept: (libc)Accepting Connections.
* access: (libc)Testing File Access.
* acos: (libc)Inverse Trig Functions.
* acosf: (libc)Inverse Trig Functions.
* acosh: (libc)Hyperbolic Functions.
* acoshf: (libc)Hyperbolic Functions.
* acoshl: (libc)Hyperbolic Functions.
* acosl: (libc)Inverse Trig Functions.
* addmntent: (libc)mtab.
* addseverity: (libc)Adding Severity Classes.
* adjtime: (libc)High-Resolution Calendar.
* adjtimex: (libc)High-Resolution Calendar.
* aio_cancel64: (libc)Cancel AIO Operations.
* aio_cancel: (libc)Cancel AIO Operations.
* aio_error64: (libc)Status of AIO Operations.
* aio_error: (libc)Status of AIO Operations.
* aio_fsync64: (libc)Synchronizing AIO Operations.
* aio_fsync: (libc)Synchronizing AIO Operations.
* aio_init: (libc)Configuration of AIO.
* aio_read64: (libc)Asynchronous Reads/Writes.
* aio_read: (libc)Asynchronous Reads/Writes.
* aio_return64: (libc)Status of AIO Operations.
* aio_return: (libc)Status of AIO Operations.
* aio_suspend64: (libc)Synchronizing AIO Operations.
* aio_suspend: (libc)Synchronizing AIO Operations.
* aio_write64: (libc)Asynchronous Reads/Writes.
* aio_write: (libc)Asynchronous Reads/Writes.
* alarm: (libc)Setting an Alarm.
* aligned_alloc: (libc)Aligned Memory Blocks.
* alloca: (libc)Variable Size Automatic.
* alphasort64: (libc)Scanning Directory Content.
* alphasort: (libc)Scanning Directory Content.
* argp_error: (libc)Argp Helper Functions.
* argp_failure: (libc)Argp Helper Functions.
* argp_help: (libc)Argp Help.
* argp_parse: (libc)Argp.
* argp_state_help: (libc)Argp Helper Functions.
* argp_usage: (libc)Argp Helper Functions.
* argz_add: (libc)Argz Functions.
* argz_add_sep: (libc)Argz Functions.
* argz_append: (libc)Argz Functions.
* argz_count: (libc)Argz Functions.
* argz_create: (libc)Argz Functions.
* argz_create_sep: (libc)Argz Functions.
* argz_delete: (libc)Argz Functions.
* argz_extract: (libc)Argz Functions.
* argz_insert: (libc)Argz Functions.
* argz_next: (libc)Argz Functions.
* argz_replace: (libc)Argz Functions.
* argz_stringify: (libc)Argz Functions.
* asctime: (libc)Formatting Calendar Time.
* asctime_r: (libc)Formatting Calendar Time.
* asin: (libc)Inverse Trig Functions.
* asinf: (libc)Inverse Trig Functions.
* asinh: (libc)Hyperbolic Functions.
* asinhf: (libc)Hyperbolic Functions.
* asinhl: (libc)Hyperbolic Functions.
* asinl: (libc)Inverse Trig Functions.
* asprintf: (libc)Dynamic Output.
* assert: (libc)Consistency Checking.
* assert_perror: (libc)Consistency Checking.
* atan2: (libc)Inverse Trig Functions.
* atan2f: (libc)Inverse Trig Functions.
* atan2l: (libc)Inverse Trig Functions.
* atan: (libc)Inverse Trig Functions.
* atanf: (libc)Inverse Trig Functions.
* atanh: (libc)Hyperbolic Functions.
* atanhf: (libc)Hyperbolic Functions.
* atanhl: (libc)Hyperbolic Functions.
* atanl: (libc)Inverse Trig Functions.
* atexit: (libc)Cleanups on Exit.
* atof: (libc)Parsing of Floats.
* atoi: (libc)Parsing of Integers.
* atol: (libc)Parsing of Integers.
* atoll: (libc)Parsing of Integers.
* backtrace: (libc)Backtraces.
* backtrace_symbols: (libc)Backtraces.
* backtrace_symbols_fd: (libc)Backtraces.
* basename: (libc)Finding Tokens in a String.
* basename: (libc)Finding Tokens in a String.
* bcmp: (libc)String/Array Comparison.
* bcopy: (libc)Copying and Concatenation.
* bind: (libc)Setting Address.
* bind_textdomain_codeset: (libc)Charset conversion in gettext.
* bindtextdomain: (libc)Locating gettext catalog.
* brk: (libc)Resizing the Data Segment.
* bsearch: (libc)Array Search Function.
* btowc: (libc)Converting a Character.
* bzero: (libc)Copying and Concatenation.
* cabs: (libc)Absolute Value.
* cabsf: (libc)Absolute Value.
* cabsl: (libc)Absolute Value.
* cacos: (libc)Inverse Trig Functions.
* cacosf: (libc)Inverse Trig Functions.
* cacosh: (libc)Hyperbolic Functions.
* cacoshf: (libc)Hyperbolic Functions.
* cacoshl: (libc)Hyperbolic Functions.
* cacosl: (libc)Inverse Trig Functions.
* calloc: (libc)Allocating Cleared Space.
* canonicalize_file_name: (libc)Symbolic Links.
* carg: (libc)Operations on Complex.
* cargf: (libc)Operations on Complex.
* cargl: (libc)Operations on Complex.
* casin: (libc)Inverse Trig Functions.
* casinf: (libc)Inverse Trig Functions.
* casinh: (libc)Hyperbolic Functions.
* casinhf: (libc)Hyperbolic Functions.
* casinhl: (libc)Hyperbolic Functions.
* casinl: (libc)Inverse Trig Functions.
* catan: (libc)Inverse Trig Functions.
* catanf: (libc)Inverse Trig Functions.
* catanh: (libc)Hyperbolic Functions.
* catanhf: (libc)Hyperbolic Functions.
* catanhl: (libc)Hyperbolic Functions.
* catanl: (libc)Inverse Trig Functions.
* catclose: (libc)The catgets Functions.
* catgets: (libc)The catgets Functions.
* catopen: (libc)The catgets Functions.
* cbc_crypt: (libc)DES Encryption.
* cbrt: (libc)Exponents and Logarithms.
* cbrtf: (libc)Exponents and Logarithms.
* cbrtl: (libc)Exponents and Logarithms.
* ccos: (libc)Trig Functions.
* ccosf: (libc)Trig Functions.
* ccosh: (libc)Hyperbolic Functions.
* ccoshf: (libc)Hyperbolic Functions.
* ccoshl: (libc)Hyperbolic Functions.
* ccosl: (libc)Trig Functions.
* ceil: (libc)Rounding Functions.
* ceilf: (libc)Rounding Functions.
* ceill: (libc)Rounding Functions.
* cexp: (libc)Exponents and Logarithms.
* cexpf: (libc)Exponents and Logarithms.
* cexpl: (libc)Exponents and Logarithms.
* cfgetispeed: (libc)Line Speed.
* cfgetospeed: (libc)Line Speed.
* cfmakeraw: (libc)Noncanonical Input.
* cfree: (libc)Freeing after Malloc.
* cfsetispeed: (libc)Line Speed.
* cfsetospeed: (libc)Line Speed.
* cfsetspeed: (libc)Line Speed.
* chdir: (libc)Working Directory.
* chmod: (libc)Setting Permissions.
* chown: (libc)File Owner.
* cimag: (libc)Operations on Complex.
* cimagf: (libc)Operations on Complex.
* cimagl: (libc)Operations on Complex.
* clearenv: (libc)Environment Access.
* clearerr: (libc)Error Recovery.
* clearerr_unlocked: (libc)Error Recovery.
* clock: (libc)CPU Time.
* clog10: (libc)Exponents and Logarithms.
* clog10f: (libc)Exponents and Logarithms.
* clog10l: (libc)Exponents and Logarithms.
* clog: (libc)Exponents and Logarithms.
* clogf: (libc)Exponents and Logarithms.
* clogl: (libc)Exponents and Logarithms.
* close: (libc)Opening and Closing Files.
* closedir: (libc)Reading/Closing Directory.
* closelog: (libc)closelog.
* confstr: (libc)String Parameters.
* conj: (libc)Operations on Complex.
* conjf: (libc)Operations on Complex.
* conjl: (libc)Operations on Complex.
* connect: (libc)Connecting.
* copysign: (libc)FP Bit Twiddling.
* copysignf: (libc)FP Bit Twiddling.
* copysignl: (libc)FP Bit Twiddling.
* cos: (libc)Trig Functions.
* cosf: (libc)Trig Functions.
* cosh: (libc)Hyperbolic Functions.
* coshf: (libc)Hyperbolic Functions.
* coshl: (libc)Hyperbolic Functions.
* cosl: (libc)Trig Functions.
* cpow: (libc)Exponents and Logarithms.
* cpowf: (libc)Exponents and Logarithms.
* cpowl: (libc)Exponents and Logarithms.
* cproj: (libc)Operations on Complex.
* cprojf: (libc)Operations on Complex.
* cprojl: (libc)Operations on Complex.
* creal: (libc)Operations on Complex.
* crealf: (libc)Operations on Complex.
* creall: (libc)Operations on Complex.
* creat64: (libc)Opening and Closing Files.
* creat: (libc)Opening and Closing Files.
* crypt: (libc)crypt.
* crypt_r: (libc)crypt.
* csin: (libc)Trig Functions.
* csinf: (libc)Trig Functions.
* csinh: (libc)Hyperbolic Functions.
* csinhf: (libc)Hyperbolic Functions.
* csinhl: (libc)Hyperbolic Functions.
* csinl: (libc)Trig Functions.
* csqrt: (libc)Exponents and Logarithms.
* csqrtf: (libc)Exponents and Logarithms.
* csqrtl: (libc)Exponents and Logarithms.
* ctan: (libc)Trig Functions.
* ctanf: (libc)Trig Functions.
* ctanh: (libc)Hyperbolic Functions.
* ctanhf: (libc)Hyperbolic Functions.
* ctanhl: (libc)Hyperbolic Functions.
* ctanl: (libc)Trig Functions.
* ctermid: (libc)Identifying the Terminal.
* ctime: (libc)Formatting Calendar Time.
* ctime_r: (libc)Formatting Calendar Time.
* cuserid: (libc)Who Logged In.
* dcgettext: (libc)Translation with gettext.
* dcngettext: (libc)Advanced gettext functions.
* des_setparity: (libc)DES Encryption.
* dgettext: (libc)Translation with gettext.
* difftime: (libc)Elapsed Time.
* dirfd: (libc)Opening a Directory.
* dirname: (libc)Finding Tokens in a String.
* div: (libc)Integer Division.
* dngettext: (libc)Advanced gettext functions.
* drand48: (libc)SVID Random.
* drand48_r: (libc)SVID Random.
* drem: (libc)Remainder Functions.
* dremf: (libc)Remainder Functions.
* dreml: (libc)Remainder Functions.
* dup2: (libc)Duplicating Descriptors.
* dup: (libc)Duplicating Descriptors.
* ecb_crypt: (libc)DES Encryption.
* ecvt: (libc)System V Number Conversion.
* ecvt_r: (libc)System V Number Conversion.
* encrypt: (libc)DES Encryption.
* encrypt_r: (libc)DES Encryption.
* endfsent: (libc)fstab.
* endgrent: (libc)Scanning All Groups.
* endhostent: (libc)Host Names.
* endmntent: (libc)mtab.
* endnetent: (libc)Networks Database.
* endnetgrent: (libc)Lookup Netgroup.
* endprotoent: (libc)Protocols Database.
* endpwent: (libc)Scanning All Users.
* endservent: (libc)Services Database.
* endutent: (libc)Manipulating the Database.
* endutxent: (libc)XPG Functions.
* envz_add: (libc)Envz Functions.
* envz_entry: (libc)Envz Functions.
* envz_get: (libc)Envz Functions.
* envz_merge: (libc)Envz Functions.
* envz_strip: (libc)Envz Functions.
* erand48: (libc)SVID Random.
* erand48_r: (libc)SVID Random.
* erf: (libc)Special Functions.
* erfc: (libc)Special Functions.
* erfcf: (libc)Special Functions.
* erfcl: (libc)Special Functions.
* erff: (libc)Special Functions.
* erfl: (libc)Special Functions.
* err: (libc)Error Messages.
* errno: (libc)Checking for Errors.
* error: (libc)Error Messages.
* error_at_line: (libc)Error Messages.
* errx: (libc)Error Messages.
* execl: (libc)Executing a File.
* execle: (libc)Executing a File.
* execlp: (libc)Executing a File.
* execv: (libc)Executing a File.
* execve: (libc)Executing a File.
* execvp: (libc)Executing a File.
* exit: (libc)Normal Termination.
* exp10: (libc)Exponents and Logarithms.
* exp10f: (libc)Exponents and Logarithms.
* exp10l: (libc)Exponents and Logarithms.
* exp2: (libc)Exponents and Logarithms.
* exp2f: (libc)Exponents and Logarithms.
* exp2l: (libc)Exponents and Logarithms.
* exp: (libc)Exponents and Logarithms.
* expf: (libc)Exponents and Logarithms.
* expl: (libc)Exponents and Logarithms.
* expm1: (libc)Exponents and Logarithms.
* expm1f: (libc)Exponents and Logarithms.
* expm1l: (libc)Exponents and Logarithms.
* fabs: (libc)Absolute Value.
* fabsf: (libc)Absolute Value.
* fabsl: (libc)Absolute Value.
* fchdir: (libc)Working Directory.
* fchmod: (libc)Setting Permissions.
* fchown: (libc)File Owner.
* fclose: (libc)Closing Streams.
* fcloseall: (libc)Closing Streams.
* fcntl: (libc)Control Operations.
* fcvt: (libc)System V Number Conversion.
* fcvt_r: (libc)System V Number Conversion.
* fdatasync: (libc)Synchronizing I/O.
* fdim: (libc)Misc FP Arithmetic.
* fdimf: (libc)Misc FP Arithmetic.
* fdiml: (libc)Misc FP Arithmetic.
* fdopen: (libc)Descriptors and Streams.
* fdopendir: (libc)Opening a Directory.
* feclearexcept: (libc)Status bit operations.
* fedisableexcept: (libc)Control Functions.
* feenableexcept: (libc)Control Functions.
* fegetenv: (libc)Control Functions.
* fegetexcept: (libc)Control Functions.
* fegetexceptflag: (libc)Status bit operations.
* fegetround: (libc)Rounding.
* feholdexcept: (libc)Control Functions.
* feof: (libc)EOF and Errors.
* feof_unlocked: (libc)EOF and Errors.
* feraiseexcept: (libc)Status bit operations.
* ferror: (libc)EOF and Errors.
* ferror_unlocked: (libc)EOF and Errors.
* fesetenv: (libc)Control Functions.
* fesetexceptflag: (libc)Status bit operations.
* fesetround: (libc)Rounding.
* fetestexcept: (libc)Status bit operations.
* feupdateenv: (libc)Control Functions.
* fflush: (libc)Flushing Buffers.
* fflush_unlocked: (libc)Flushing Buffers.
* fgetc: (libc)Character Input.
* fgetc_unlocked: (libc)Character Input.
* fgetgrent: (libc)Scanning All Groups.
* fgetgrent_r: (libc)Scanning All Groups.
* fgetpos64: (libc)Portable Positioning.
* fgetpos: (libc)Portable Positioning.
* fgetpwent: (libc)Scanning All Users.
* fgetpwent_r: (libc)Scanning All Users.
* fgets: (libc)Line Input.
* fgets_unlocked: (libc)Line Input.
* fgetwc: (libc)Character Input.
* fgetwc_unlocked: (libc)Character Input.
* fgetws: (libc)Line Input.
* fgetws_unlocked: (libc)Line Input.
* fileno: (libc)Descriptors and Streams.
* fileno_unlocked: (libc)Descriptors and Streams.
* finite: (libc)Floating Point Classes.
* finitef: (libc)Floating Point Classes.
* finitel: (libc)Floating Point Classes.
* flockfile: (libc)Streams and Threads.
* floor: (libc)Rounding Functions.
* floorf: (libc)Rounding Functions.
* floorl: (libc)Rounding Functions.
* fma: (libc)Misc FP Arithmetic.
* fmaf: (libc)Misc FP Arithmetic.
* fmal: (libc)Misc FP Arithmetic.
* fmax: (libc)Misc FP Arithmetic.
* fmaxf: (libc)Misc FP Arithmetic.
* fmaxl: (libc)Misc FP Arithmetic.
* fmemopen: (libc)String Streams.
* fmin: (libc)Misc FP Arithmetic.
* fminf: (libc)Misc FP Arithmetic.
* fminl: (libc)Misc FP Arithmetic.
* fmod: (libc)Remainder Functions.
* fmodf: (libc)Remainder Functions.
* fmodl: (libc)Remainder Functions.
* fmtmsg: (libc)Printing Formatted Messages.
* fnmatch: (libc)Wildcard Matching.
* fopen64: (libc)Opening Streams.
* fopen: (libc)Opening Streams.
* fopencookie: (libc)Streams and Cookies.
* fork: (libc)Creating a Process.
* forkpty: (libc)Pseudo-Terminal Pairs.
* fpathconf: (libc)Pathconf.
* fpclassify: (libc)Floating Point Classes.
* fprintf: (libc)Formatted Output Functions.
* fputc: (libc)Simple Output.
* fputc_unlocked: (libc)Simple Output.
* fputs: (libc)Simple Output.
* fputs_unlocked: (libc)Simple Output.
* fputwc: (libc)Simple Output.
* fputwc_unlocked: (libc)Simple Output.
* fputws: (libc)Simple Output.
* fputws_unlocked: (libc)Simple Output.
* fread: (libc)Block Input/Output.
* fread_unlocked: (libc)Block Input/Output.
* free: (libc)Freeing after Malloc.
* freopen64: (libc)Opening Streams.
* freopen: (libc)Opening Streams.
* frexp: (libc)Normalization Functions.
* frexpf: (libc)Normalization Functions.
* frexpl: (libc)Normalization Functions.
* fscanf: (libc)Formatted Input Functions.
* fseek: (libc)File Positioning.
* fseeko64: (libc)File Positioning.
* fseeko: (libc)File Positioning.
* fsetpos64: (libc)Portable Positioning.
* fsetpos: (libc)Portable Positioning.
* fstat64: (libc)Reading Attributes.
* fstat: (libc)Reading Attributes.
* fsync: (libc)Synchronizing I/O.
* ftell: (libc)File Positioning.
* ftello64: (libc)File Positioning.
* ftello: (libc)File Positioning.
* ftruncate64: (libc)File Size.
* ftruncate: (libc)File Size.
* ftrylockfile: (libc)Streams and Threads.
* ftw64: (libc)Working with Directory Trees.
* ftw: (libc)Working with Directory Trees.
* funlockfile: (libc)Streams and Threads.
* futimes: (libc)File Times.
* fwide: (libc)Streams and I18N.
* fwprintf: (libc)Formatted Output Functions.
* fwrite: (libc)Block Input/Output.
* fwrite_unlocked: (libc)Block Input/Output.
* fwscanf: (libc)Formatted Input Functions.
* gamma: (libc)Special Functions.
* gammaf: (libc)Special Functions.
* gammal: (libc)Special Functions.
* gcvt: (libc)System V Number Conversion.
* get_avphys_pages: (libc)Query Memory Parameters.
* get_current_dir_name: (libc)Working Directory.
* get_nprocs: (libc)Processor Resources.
* get_nprocs_conf: (libc)Processor Resources.
* get_phys_pages: (libc)Query Memory Parameters.
* getauxval: (libc)Auxiliary Vector.
* getc: (libc)Character Input.
* getc_unlocked: (libc)Character Input.
* getchar: (libc)Character Input.
* getchar_unlocked: (libc)Character Input.
* getcontext: (libc)System V contexts.
* getcwd: (libc)Working Directory.
* getdate: (libc)General Time String Parsing.
* getdate_r: (libc)General Time String Parsing.
* getdelim: (libc)Line Input.
* getdomainnname: (libc)Host Identification.
* getegid: (libc)Reading Persona.
* getenv: (libc)Environment Access.
* geteuid: (libc)Reading Persona.
* getfsent: (libc)fstab.
* getfsfile: (libc)fstab.
* getfsspec: (libc)fstab.
* getgid: (libc)Reading Persona.
* getgrent: (libc)Scanning All Groups.
* getgrent_r: (libc)Scanning All Groups.
* getgrgid: (libc)Lookup Group.
* getgrgid_r: (libc)Lookup Group.
* getgrnam: (libc)Lookup Group.
* getgrnam_r: (libc)Lookup Group.
* getgrouplist: (libc)Setting Groups.
* getgroups: (libc)Reading Persona.
* gethostbyaddr: (libc)Host Names.
* gethostbyaddr_r: (libc)Host Names.
* gethostbyname2: (libc)Host Names.
* gethostbyname2_r: (libc)Host Names.
* gethostbyname: (libc)Host Names.
* gethostbyname_r: (libc)Host Names.
* gethostent: (libc)Host Names.
* gethostid: (libc)Host Identification.
* gethostname: (libc)Host Identification.
* getitimer: (libc)Setting an Alarm.
* getline: (libc)Line Input.
* getloadavg: (libc)Processor Resources.
* getlogin: (libc)Who Logged In.
* getmntent: (libc)mtab.
* getmntent_r: (libc)mtab.
* getnetbyaddr: (libc)Networks Database.
* getnetbyname: (libc)Networks Database.
* getnetent: (libc)Networks Database.
* getnetgrent: (libc)Lookup Netgroup.
* getnetgrent_r: (libc)Lookup Netgroup.
* getopt: (libc)Using Getopt.
* getopt_long: (libc)Getopt Long Options.
* getopt_long_only: (libc)Getopt Long Options.
* getpagesize: (libc)Query Memory Parameters.
* getpass: (libc)getpass.
* getpeername: (libc)Who is Connected.
* getpgid: (libc)Process Group Functions.
* getpgrp: (libc)Process Group Functions.
* getpid: (libc)Process Identification.
* getppid: (libc)Process Identification.
* getpriority: (libc)Traditional Scheduling Functions.
* getprotobyname: (libc)Protocols Database.
* getprotobynumber: (libc)Protocols Database.
* getprotoent: (libc)Protocols Database.
* getpt: (libc)Allocation.
* getpwent: (libc)Scanning All Users.
* getpwent_r: (libc)Scanning All Users.
* getpwnam: (libc)Lookup User.
* getpwnam_r: (libc)Lookup User.
* getpwuid: (libc)Lookup User.
* getpwuid_r: (libc)Lookup User.
* getrlimit64: (libc)Limits on Resources.
* getrlimit: (libc)Limits on Resources.
* getrusage: (libc)Resource Usage.
* gets: (libc)Line Input.
* getservbyname: (libc)Services Database.
* getservbyport: (libc)Services Database.
* getservent: (libc)Services Database.
* getsid: (libc)Process Group Functions.
* getsockname: (libc)Reading Address.
* getsockopt: (libc)Socket Option Functions.
* getsubopt: (libc)Suboptions.
* gettext: (libc)Translation with gettext.
* gettimeofday: (libc)High-Resolution Calendar.
* getuid: (libc)Reading Persona.
* getumask: (libc)Setting Permissions.
* getutent: (libc)Manipulating the Database.
* getutent_r: (libc)Manipulating the Database.
* getutid: (libc)Manipulating the Database.
* getutid_r: (libc)Manipulating the Database.
* getutline: (libc)Manipulating the Database.
* getutline_r: (libc)Manipulating the Database.
* getutmp: (libc)XPG Functions.
* getutmpx: (libc)XPG Functions.
* getutxent: (libc)XPG Functions.
* getutxid: (libc)XPG Functions.
* getutxline: (libc)XPG Functions.
* getw: (libc)Character Input.
* getwc: (libc)Character Input.
* getwc_unlocked: (libc)Character Input.
* getwchar: (libc)Character Input.
* getwchar_unlocked: (libc)Character Input.
* getwd: (libc)Working Directory.
* glob64: (libc)Calling Glob.
* glob: (libc)Calling Glob.
* globfree64: (libc)More Flags for Globbing.
* globfree: (libc)More Flags for Globbing.
* gmtime: (libc)Broken-down Time.
* gmtime_r: (libc)Broken-down Time.
* grantpt: (libc)Allocation.
* gsignal: (libc)Signaling Yourself.
* gtty: (libc)BSD Terminal Modes.
* hasmntopt: (libc)mtab.
* hcreate: (libc)Hash Search Function.
* hcreate_r: (libc)Hash Search Function.
* hdestroy: (libc)Hash Search Function.
* hdestroy_r: (libc)Hash Search Function.
* hsearch: (libc)Hash Search Function.
* hsearch_r: (libc)Hash Search Function.
* htonl: (libc)Byte Order.
* htons: (libc)Byte Order.
* hypot: (libc)Exponents and Logarithms.
* hypotf: (libc)Exponents and Logarithms.
* hypotl: (libc)Exponents and Logarithms.
* iconv: (libc)Generic Conversion Interface.
* iconv_close: (libc)Generic Conversion Interface.
* iconv_open: (libc)Generic Conversion Interface.
* if_freenameindex: (libc)Interface Naming.
* if_indextoname: (libc)Interface Naming.
* if_nameindex: (libc)Interface Naming.
* if_nametoindex: (libc)Interface Naming.
* ilogb: (libc)Exponents and Logarithms.
* ilogbf: (libc)Exponents and Logarithms.
* ilogbl: (libc)Exponents and Logarithms.
* imaxabs: (libc)Absolute Value.
* imaxdiv: (libc)Integer Division.
* in6addr_any: (libc)Host Address Data Type.
* in6addr_loopback: (libc)Host Address Data Type.
* index: (libc)Search Functions.
* inet_addr: (libc)Host Address Functions.
* inet_aton: (libc)Host Address Functions.
* inet_lnaof: (libc)Host Address Functions.
* inet_makeaddr: (libc)Host Address Functions.
* inet_netof: (libc)Host Address Functions.
* inet_network: (libc)Host Address Functions.
* inet_ntoa: (libc)Host Address Functions.
* inet_ntop: (libc)Host Address Functions.
* inet_pton: (libc)Host Address Functions.
* initgroups: (libc)Setting Groups.
* initstate: (libc)BSD Random.
* initstate_r: (libc)BSD Random.
* innetgr: (libc)Netgroup Membership.
* ioctl: (libc)IOCTLs.
* isalnum: (libc)Classification of Characters.
* isalpha: (libc)Classification of Characters.
* isascii: (libc)Classification of Characters.
* isatty: (libc)Is It a Terminal.
* isblank: (libc)Classification of Characters.
* iscntrl: (libc)Classification of Characters.
* isdigit: (libc)Classification of Characters.
* isfinite: (libc)Floating Point Classes.
* isgraph: (libc)Classification of Characters.
* isgreater: (libc)FP Comparison Functions.
* isgreaterequal: (libc)FP Comparison Functions.
* isinf: (libc)Floating Point Classes.
* isinff: (libc)Floating Point Classes.
* isinfl: (libc)Floating Point Classes.
* isless: (libc)FP Comparison Functions.
* islessequal: (libc)FP Comparison Functions.
* islessgreater: (libc)FP Comparison Functions.
* islower: (libc)Classification of Characters.
* isnan: (libc)Floating Point Classes.
* isnan: (libc)Floating Point Classes.
* isnanf: (libc)Floating Point Classes.
* isnanl: (libc)Floating Point Classes.
* isnormal: (libc)Floating Point Classes.
* isprint: (libc)Classification of Characters.
* ispunct: (libc)Classification of Characters.
* issignaling: (libc)Floating Point Classes.
* isspace: (libc)Classification of Characters.
* isunordered: (libc)FP Comparison Functions.
* isupper: (libc)Classification of Characters.
* iswalnum: (libc)Classification of Wide Characters.
* iswalpha: (libc)Classification of Wide Characters.
* iswblank: (libc)Classification of Wide Characters.
* iswcntrl: (libc)Classification of Wide Characters.
* iswctype: (libc)Classification of Wide Characters.
* iswdigit: (libc)Classification of Wide Characters.
* iswgraph: (libc)Classification of Wide Characters.
* iswlower: (libc)Classification of Wide Characters.
* iswprint: (libc)Classification of Wide Characters.
* iswpunct: (libc)Classification of Wide Characters.
* iswspace: (libc)Classification of Wide Characters.
* iswupper: (libc)Classification of Wide Characters.
* iswxdigit: (libc)Classification of Wide Characters.
* isxdigit: (libc)Classification of Characters.
* j0: (libc)Special Functions.
* j0f: (libc)Special Functions.
* j0l: (libc)Special Functions.
* j1: (libc)Special Functions.
* j1f: (libc)Special Functions.
* j1l: (libc)Special Functions.
* jn: (libc)Special Functions.
* jnf: (libc)Special Functions.
* jnl: (libc)Special Functions.
* jrand48: (libc)SVID Random.
* jrand48_r: (libc)SVID Random.
* kill: (libc)Signaling Another Process.
* killpg: (libc)Signaling Another Process.
* l64a: (libc)Encode Binary Data.
* labs: (libc)Absolute Value.
* lcong48: (libc)SVID Random.
* lcong48_r: (libc)SVID Random.
* ldexp: (libc)Normalization Functions.
* ldexpf: (libc)Normalization Functions.
* ldexpl: (libc)Normalization Functions.
* ldiv: (libc)Integer Division.
* lfind: (libc)Array Search Function.
* lgamma: (libc)Special Functions.
* lgamma_r: (libc)Special Functions.
* lgammaf: (libc)Special Functions.
* lgammaf_r: (libc)Special Functions.
* lgammal: (libc)Special Functions.
* lgammal_r: (libc)Special Functions.
* link: (libc)Hard Links.
* lio_listio64: (libc)Asynchronous Reads/Writes.
* lio_listio: (libc)Asynchronous Reads/Writes.
* listen: (libc)Listening.
* llabs: (libc)Absolute Value.
* lldiv: (libc)Integer Division.
* llrint: (libc)Rounding Functions.
* llrintf: (libc)Rounding Functions.
* llrintl: (libc)Rounding Functions.
* llround: (libc)Rounding Functions.
* llroundf: (libc)Rounding Functions.
* llroundl: (libc)Rounding Functions.
* localeconv: (libc)The Lame Way to Locale Data.
* localtime: (libc)Broken-down Time.
* localtime_r: (libc)Broken-down Time.
* log10: (libc)Exponents and Logarithms.
* log10f: (libc)Exponents and Logarithms.
* log10l: (libc)Exponents and Logarithms.
* log1p: (libc)Exponents and Logarithms.
* log1pf: (libc)Exponents and Logarithms.
* log1pl: (libc)Exponents and Logarithms.
* log2: (libc)Exponents and Logarithms.
* log2f: (libc)Exponents and Logarithms.
* log2l: (libc)Exponents and Logarithms.
* log: (libc)Exponents and Logarithms.
* logb: (libc)Exponents and Logarithms.
* logbf: (libc)Exponents and Logarithms.
* logbl: (libc)Exponents and Logarithms.
* logf: (libc)Exponents and Logarithms.
* login: (libc)Logging In and Out.
* login_tty: (libc)Logging In and Out.
* logl: (libc)Exponents and Logarithms.
* logout: (libc)Logging In and Out.
* logwtmp: (libc)Logging In and Out.
* longjmp: (libc)Non-Local Details.
* lrand48: (libc)SVID Random.
* lrand48_r: (libc)SVID Random.
* lrint: (libc)Rounding Functions.
* lrintf: (libc)Rounding Functions.
* lrintl: (libc)Rounding Functions.
* lround: (libc)Rounding Functions.
* lroundf: (libc)Rounding Functions.
* lroundl: (libc)Rounding Functions.
* lsearch: (libc)Array Search Function.
* lseek64: (libc)File Position Primitive.
* lseek: (libc)File Position Primitive.
* lstat64: (libc)Reading Attributes.
* lstat: (libc)Reading Attributes.
* lutimes: (libc)File Times.
* madvise: (libc)Memory-mapped I/O.
* makecontext: (libc)System V contexts.
* mallinfo: (libc)Statistics of Malloc.
* malloc: (libc)Basic Allocation.
* mallopt: (libc)Malloc Tunable Parameters.
* mblen: (libc)Non-reentrant Character Conversion.
* mbrlen: (libc)Converting a Character.
* mbrtowc: (libc)Converting a Character.
* mbsinit: (libc)Keeping the state.
* mbsnrtowcs: (libc)Converting Strings.
* mbsrtowcs: (libc)Converting Strings.
* mbstowcs: (libc)Non-reentrant String Conversion.
* mbtowc: (libc)Non-reentrant Character Conversion.
* mcheck: (libc)Heap Consistency Checking.
* memalign: (libc)Aligned Memory Blocks.
* memccpy: (libc)Copying and Concatenation.
* memchr: (libc)Search Functions.
* memcmp: (libc)String/Array Comparison.
* memcpy: (libc)Copying and Concatenation.
* memfrob: (libc)Trivial Encryption.
* memmem: (libc)Search Functions.
* memmove: (libc)Copying and Concatenation.
* mempcpy: (libc)Copying and Concatenation.
* memrchr: (libc)Search Functions.
* memset: (libc)Copying and Concatenation.
* mkdir: (libc)Creating Directories.
* mkdtemp: (libc)Temporary Files.
* mkfifo: (libc)FIFO Special Files.
* mknod: (libc)Making Special Files.
* mkstemp: (libc)Temporary Files.
* mktemp: (libc)Temporary Files.
* mktime: (libc)Broken-down Time.
* mlock: (libc)Page Lock Functions.
* mlockall: (libc)Page Lock Functions.
* mmap64: (libc)Memory-mapped I/O.
* mmap: (libc)Memory-mapped I/O.
* modf: (libc)Rounding Functions.
* modff: (libc)Rounding Functions.
* modfl: (libc)Rounding Functions.
* mount: (libc)Mount-Unmount-Remount.
* mprobe: (libc)Heap Consistency Checking.
* mrand48: (libc)SVID Random.
* mrand48_r: (libc)SVID Random.
* mremap: (libc)Memory-mapped I/O.
* msync: (libc)Memory-mapped I/O.
* mtrace: (libc)Tracing malloc.
* munlock: (libc)Page Lock Functions.
* munlockall: (libc)Page Lock Functions.
* munmap: (libc)Memory-mapped I/O.
* muntrace: (libc)Tracing malloc.
* nan: (libc)FP Bit Twiddling.
* nanf: (libc)FP Bit Twiddling.
* nanl: (libc)FP Bit Twiddling.
* nanosleep: (libc)Sleeping.
* nearbyint: (libc)Rounding Functions.
* nearbyintf: (libc)Rounding Functions.
* nearbyintl: (libc)Rounding Functions.
* nextafter: (libc)FP Bit Twiddling.
* nextafterf: (libc)FP Bit Twiddling.
* nextafterl: (libc)FP Bit Twiddling.
* nexttoward: (libc)FP Bit Twiddling.
* nexttowardf: (libc)FP Bit Twiddling.
* nexttowardl: (libc)FP Bit Twiddling.
* nftw64: (libc)Working with Directory Trees.
* nftw: (libc)Working with Directory Trees.
* ngettext: (libc)Advanced gettext functions.
* nice: (libc)Traditional Scheduling Functions.
* nl_langinfo: (libc)The Elegant and Fast Way.
* nrand48: (libc)SVID Random.
* nrand48_r: (libc)SVID Random.
* ntohl: (libc)Byte Order.
* ntohs: (libc)Byte Order.
* ntp_adjtime: (libc)High Accuracy Clock.
* ntp_gettime: (libc)High Accuracy Clock.
* obstack_1grow: (libc)Growing Objects.
* obstack_1grow_fast: (libc)Extra Fast Growing.
* obstack_alignment_mask: (libc)Obstacks Data Alignment.
* obstack_alloc: (libc)Allocation in an Obstack.
* obstack_base: (libc)Status of an Obstack.
* obstack_blank: (libc)Growing Objects.
* obstack_blank_fast: (libc)Extra Fast Growing.
* obstack_chunk_size: (libc)Obstack Chunks.
* obstack_copy0: (libc)Allocation in an Obstack.
* obstack_copy: (libc)Allocation in an Obstack.
* obstack_finish: (libc)Growing Objects.
* obstack_free: (libc)Freeing Obstack Objects.
* obstack_grow0: (libc)Growing Objects.
* obstack_grow: (libc)Growing Objects.
* obstack_init: (libc)Preparing for Obstacks.
* obstack_int_grow: (libc)Growing Objects.
* obstack_int_grow_fast: (libc)Extra Fast Growing.
* obstack_next_free: (libc)Status of an Obstack.
* obstack_object_size: (libc)Growing Objects.
* obstack_object_size: (libc)Status of an Obstack.
* obstack_printf: (libc)Dynamic Output.
* obstack_ptr_grow: (libc)Growing Objects.
* obstack_ptr_grow_fast: (libc)Extra Fast Growing.
* obstack_room: (libc)Extra Fast Growing.
* obstack_vprintf: (libc)Variable Arguments Output.
* offsetof: (libc)Structure Measurement.
* on_exit: (libc)Cleanups on Exit.
* open64: (libc)Opening and Closing Files.
* open: (libc)Opening and Closing Files.
* open_memstream: (libc)String Streams.
* opendir: (libc)Opening a Directory.
* openlog: (libc)openlog.
* openpty: (libc)Pseudo-Terminal Pairs.
* parse_printf_format: (libc)Parsing a Template String.
* pathconf: (libc)Pathconf.
* pause: (libc)Using Pause.
* pclose: (libc)Pipe to a Subprocess.
* perror: (libc)Error Messages.
* pipe: (libc)Creating a Pipe.
* popen: (libc)Pipe to a Subprocess.
* posix_memalign: (libc)Aligned Memory Blocks.
* pow10: (libc)Exponents and Logarithms.
* pow10f: (libc)Exponents and Logarithms.
* pow10l: (libc)Exponents and Logarithms.
* pow: (libc)Exponents and Logarithms.
* powf: (libc)Exponents and Logarithms.
* powl: (libc)Exponents and Logarithms.
* pread64: (libc)I/O Primitives.
* pread: (libc)I/O Primitives.
* printf: (libc)Formatted Output Functions.
* printf_size: (libc)Predefined Printf Handlers.
* printf_size_info: (libc)Predefined Printf Handlers.
* psignal: (libc)Signal Messages.
* pthread_getattr_default_np: (libc)Default Thread Attributes.
* pthread_getspecific: (libc)Thread-specific Data.
* pthread_key_create: (libc)Thread-specific Data.
* pthread_key_delete: (libc)Thread-specific Data.
* pthread_setattr_default_np: (libc)Default Thread Attributes.
* pthread_setspecific: (libc)Thread-specific Data.
* ptsname: (libc)Allocation.
* ptsname_r: (libc)Allocation.
* putc: (libc)Simple Output.
* putc_unlocked: (libc)Simple Output.
* putchar: (libc)Simple Output.
* putchar_unlocked: (libc)Simple Output.
* putenv: (libc)Environment Access.
* putpwent: (libc)Writing a User Entry.
* puts: (libc)Simple Output.
* pututline: (libc)Manipulating the Database.
* pututxline: (libc)XPG Functions.
* putw: (libc)Simple Output.
* putwc: (libc)Simple Output.
* putwc_unlocked: (libc)Simple Output.
* putwchar: (libc)Simple Output.
* putwchar_unlocked: (libc)Simple Output.
* pwrite64: (libc)I/O Primitives.
* pwrite: (libc)I/O Primitives.
* qecvt: (libc)System V Number Conversion.
* qecvt_r: (libc)System V Number Conversion.
* qfcvt: (libc)System V Number Conversion.
* qfcvt_r: (libc)System V Number Conversion.
* qgcvt: (libc)System V Number Conversion.
* qsort: (libc)Array Sort Function.
* raise: (libc)Signaling Yourself.
* rand: (libc)ISO Random.
* rand_r: (libc)ISO Random.
* random: (libc)BSD Random.
* random_r: (libc)BSD Random.
* rawmemchr: (libc)Search Functions.
* read: (libc)I/O Primitives.
* readdir64: (libc)Reading/Closing Directory.
* readdir64_r: (libc)Reading/Closing Directory.
* readdir: (libc)Reading/Closing Directory.
* readdir_r: (libc)Reading/Closing Directory.
* readlink: (libc)Symbolic Links.
* readv: (libc)Scatter-Gather.
* realloc: (libc)Changing Block Size.
* realpath: (libc)Symbolic Links.
* recv: (libc)Receiving Data.
* recvfrom: (libc)Receiving Datagrams.
* recvmsg: (libc)Receiving Datagrams.
* regcomp: (libc)POSIX Regexp Compilation.
* regerror: (libc)Regexp Cleanup.
* regexec: (libc)Matching POSIX Regexps.
* regfree: (libc)Regexp Cleanup.
* register_printf_function: (libc)Registering New Conversions.
* remainder: (libc)Remainder Functions.
* remainderf: (libc)Remainder Functions.
* remainderl: (libc)Remainder Functions.
* remove: (libc)Deleting Files.
* rename: (libc)Renaming Files.
* rewind: (libc)File Positioning.
* rewinddir: (libc)Random Access Directory.
* rindex: (libc)Search Functions.
* rint: (libc)Rounding Functions.
* rintf: (libc)Rounding Functions.
* rintl: (libc)Rounding Functions.
* rmdir: (libc)Deleting Files.
* round: (libc)Rounding Functions.
* roundf: (libc)Rounding Functions.
* roundl: (libc)Rounding Functions.
* rpmatch: (libc)Yes-or-No Questions.
* sbrk: (libc)Resizing the Data Segment.
* scalb: (libc)Normalization Functions.
* scalbf: (libc)Normalization Functions.
* scalbl: (libc)Normalization Functions.
* scalbln: (libc)Normalization Functions.
* scalblnf: (libc)Normalization Functions.
* scalblnl: (libc)Normalization Functions.
* scalbn: (libc)Normalization Functions.
* scalbnf: (libc)Normalization Functions.
* scalbnl: (libc)Normalization Functions.
* scandir64: (libc)Scanning Directory Content.
* scandir: (libc)Scanning Directory Content.
* scanf: (libc)Formatted Input Functions.
* sched_get_priority_max: (libc)Basic Scheduling Functions.
* sched_get_priority_min: (libc)Basic Scheduling Functions.
* sched_getaffinity: (libc)CPU Affinity.
* sched_getparam: (libc)Basic Scheduling Functions.
* sched_getscheduler: (libc)Basic Scheduling Functions.
* sched_rr_get_interval: (libc)Basic Scheduling Functions.
* sched_setaffinity: (libc)CPU Affinity.
* sched_setparam: (libc)Basic Scheduling Functions.
* sched_setscheduler: (libc)Basic Scheduling Functions.
* sched_yield: (libc)Basic Scheduling Functions.
* secure_getenv: (libc)Environment Access.
* seed48: (libc)SVID Random.
* seed48_r: (libc)SVID Random.
* seekdir: (libc)Random Access Directory.
* select: (libc)Waiting for I/O.
* send: (libc)Sending Data.
* sendmsg: (libc)Receiving Datagrams.
* sendto: (libc)Sending Datagrams.
* setbuf: (libc)Controlling Buffering.
* setbuffer: (libc)Controlling Buffering.
* setcontext: (libc)System V contexts.
* setdomainname: (libc)Host Identification.
* setegid: (libc)Setting Groups.
* setenv: (libc)Environment Access.
* seteuid: (libc)Setting User ID.
* setfsent: (libc)fstab.
* setgid: (libc)Setting Groups.
* setgrent: (libc)Scanning All Groups.
* setgroups: (libc)Setting Groups.
* sethostent: (libc)Host Names.
* sethostid: (libc)Host Identification.
* sethostname: (libc)Host Identification.
* setitimer: (libc)Setting an Alarm.
* setjmp: (libc)Non-Local Details.
* setkey: (libc)DES Encryption.
* setkey_r: (libc)DES Encryption.
* setlinebuf: (libc)Controlling Buffering.
* setlocale: (libc)Setting the Locale.
* setlogmask: (libc)setlogmask.
* setmntent: (libc)mtab.
* setnetent: (libc)Networks Database.
* setnetgrent: (libc)Lookup Netgroup.
* setpgid: (libc)Process Group Functions.
* setpgrp: (libc)Process Group Functions.
* setpriority: (libc)Traditional Scheduling Functions.
* setprotoent: (libc)Protocols Database.
* setpwent: (libc)Scanning All Users.
* setregid: (libc)Setting Groups.
* setreuid: (libc)Setting User ID.
* setrlimit64: (libc)Limits on Resources.
* setrlimit: (libc)Limits on Resources.
* setservent: (libc)Services Database.
* setsid: (libc)Process Group Functions.
* setsockopt: (libc)Socket Option Functions.
* setstate: (libc)BSD Random.
* setstate_r: (libc)BSD Random.
* settimeofday: (libc)High-Resolution Calendar.
* setuid: (libc)Setting User ID.
* setutent: (libc)Manipulating the Database.
* setutxent: (libc)XPG Functions.
* setvbuf: (libc)Controlling Buffering.
* shm_open: (libc)Memory-mapped I/O.
* shm_unlink: (libc)Memory-mapped I/O.
* shutdown: (libc)Closing a Socket.
* sigaction: (libc)Advanced Signal Handling.
* sigaddset: (libc)Signal Sets.
* sigaltstack: (libc)Signal Stack.
* sigblock: (libc)Blocking in BSD.
* sigdelset: (libc)Signal Sets.
* sigemptyset: (libc)Signal Sets.
* sigfillset: (libc)Signal Sets.
* siginterrupt: (libc)BSD Handler.
* sigismember: (libc)Signal Sets.
* siglongjmp: (libc)Non-Local Exits and Signals.
* sigmask: (libc)Blocking in BSD.
* signal: (libc)Basic Signal Handling.
* signbit: (libc)FP Bit Twiddling.
* significand: (libc)Normalization Functions.
* significandf: (libc)Normalization Functions.
* significandl: (libc)Normalization Functions.
* sigpause: (libc)Blocking in BSD.
* sigpending: (libc)Checking for Pending Signals.
* sigprocmask: (libc)Process Signal Mask.
* sigsetjmp: (libc)Non-Local Exits and Signals.
* sigsetmask: (libc)Blocking in BSD.
* sigstack: (libc)Signal Stack.
* sigsuspend: (libc)Sigsuspend.
* sigvec: (libc)BSD Handler.
* sin: (libc)Trig Functions.
* sincos: (libc)Trig Functions.
* sincosf: (libc)Trig Functions.
* sincosl: (libc)Trig Functions.
* sinf: (libc)Trig Functions.
* sinh: (libc)Hyperbolic Functions.
* sinhf: (libc)Hyperbolic Functions.
* sinhl: (libc)Hyperbolic Functions.
* sinl: (libc)Trig Functions.
* sleep: (libc)Sleeping.
* snprintf: (libc)Formatted Output Functions.
* socket: (libc)Creating a Socket.
* socketpair: (libc)Socket Pairs.
* sprintf: (libc)Formatted Output Functions.
* sqrt: (libc)Exponents and Logarithms.
* sqrtf: (libc)Exponents and Logarithms.
* sqrtl: (libc)Exponents and Logarithms.
* srand48: (libc)SVID Random.
* srand48_r: (libc)SVID Random.
* srand: (libc)ISO Random.
* srandom: (libc)BSD Random.
* srandom_r: (libc)BSD Random.
* sscanf: (libc)Formatted Input Functions.
* ssignal: (libc)Basic Signal Handling.
* stat64: (libc)Reading Attributes.
* stat: (libc)Reading Attributes.
* stime: (libc)Simple Calendar Time.
* stpcpy: (libc)Copying and Concatenation.
* stpncpy: (libc)Copying and Concatenation.
* strcasecmp: (libc)String/Array Comparison.
* strcasestr: (libc)Search Functions.
* strcat: (libc)Copying and Concatenation.
* strchr: (libc)Search Functions.
* strchrnul: (libc)Search Functions.
* strcmp: (libc)String/Array Comparison.
* strcoll: (libc)Collation Functions.
* strcpy: (libc)Copying and Concatenation.
* strcspn: (libc)Search Functions.
* strdup: (libc)Copying and Concatenation.
* strdupa: (libc)Copying and Concatenation.
* strerror: (libc)Error Messages.
* strerror_r: (libc)Error Messages.
* strfmon: (libc)Formatting Numbers.
* strfry: (libc)strfry.
* strftime: (libc)Formatting Calendar Time.
* strlen: (libc)String Length.
* strncasecmp: (libc)String/Array Comparison.
* strncat: (libc)Copying and Concatenation.
* strncmp: (libc)String/Array Comparison.
* strncpy: (libc)Copying and Concatenation.
* strndup: (libc)Copying and Concatenation.
* strndupa: (libc)Copying and Concatenation.
* strnlen: (libc)String Length.
* strpbrk: (libc)Search Functions.
* strptime: (libc)Low-Level Time String Parsing.
* strrchr: (libc)Search Functions.
* strsep: (libc)Finding Tokens in a String.
* strsignal: (libc)Signal Messages.
* strspn: (libc)Search Functions.
* strstr: (libc)Search Functions.
* strtod: (libc)Parsing of Floats.
* strtof: (libc)Parsing of Floats.
* strtoimax: (libc)Parsing of Integers.
* strtok: (libc)Finding Tokens in a String.
* strtok_r: (libc)Finding Tokens in a String.
* strtol: (libc)Parsing of Integers.
* strtold: (libc)Parsing of Floats.
* strtoll: (libc)Parsing of Integers.
* strtoq: (libc)Parsing of Integers.
* strtoul: (libc)Parsing of Integers.
* strtoull: (libc)Parsing of Integers.
* strtoumax: (libc)Parsing of Integers.
* strtouq: (libc)Parsing of Integers.
* strverscmp: (libc)String/Array Comparison.
* strxfrm: (libc)Collation Functions.
* stty: (libc)BSD Terminal Modes.
* swapcontext: (libc)System V contexts.
* swprintf: (libc)Formatted Output Functions.
* swscanf: (libc)Formatted Input Functions.
* symlink: (libc)Symbolic Links.
* sync: (libc)Synchronizing I/O.
* syscall: (libc)System Calls.
* sysconf: (libc)Sysconf Definition.
* sysctl: (libc)System Parameters.
* syslog: (libc)syslog; vsyslog.
* system: (libc)Running a Command.
* sysv_signal: (libc)Basic Signal Handling.
* tan: (libc)Trig Functions.
* tanf: (libc)Trig Functions.
* tanh: (libc)Hyperbolic Functions.
* tanhf: (libc)Hyperbolic Functions.
* tanhl: (libc)Hyperbolic Functions.
* tanl: (libc)Trig Functions.
* tcdrain: (libc)Line Control.
* tcflow: (libc)Line Control.
* tcflush: (libc)Line Control.
* tcgetattr: (libc)Mode Functions.
* tcgetpgrp: (libc)Terminal Access Functions.
* tcgetsid: (libc)Terminal Access Functions.
* tcsendbreak: (libc)Line Control.
* tcsetattr: (libc)Mode Functions.
* tcsetpgrp: (libc)Terminal Access Functions.
* tdelete: (libc)Tree Search Function.
* tdestroy: (libc)Tree Search Function.
* telldir: (libc)Random Access Directory.
* tempnam: (libc)Temporary Files.
* textdomain: (libc)Locating gettext catalog.
* tfind: (libc)Tree Search Function.
* tgamma: (libc)Special Functions.
* tgammaf: (libc)Special Functions.
* tgammal: (libc)Special Functions.
* time: (libc)Simple Calendar Time.
* timegm: (libc)Broken-down Time.
* timelocal: (libc)Broken-down Time.
* times: (libc)Processor Time.
* tmpfile64: (libc)Temporary Files.
* tmpfile: (libc)Temporary Files.
* tmpnam: (libc)Temporary Files.
* tmpnam_r: (libc)Temporary Files.
* toascii: (libc)Case Conversion.
* tolower: (libc)Case Conversion.
* toupper: (libc)Case Conversion.
* towctrans: (libc)Wide Character Case Conversion.
* towlower: (libc)Wide Character Case Conversion.
* towupper: (libc)Wide Character Case Conversion.
* trunc: (libc)Rounding Functions.
* truncate64: (libc)File Size.
* truncate: (libc)File Size.
* truncf: (libc)Rounding Functions.
* truncl: (libc)Rounding Functions.
* tsearch: (libc)Tree Search Function.
* ttyname: (libc)Is It a Terminal.
* ttyname_r: (libc)Is It a Terminal.
* twalk: (libc)Tree Search Function.
* tzset: (libc)Time Zone Functions.
* ulimit: (libc)Limits on Resources.
* umask: (libc)Setting Permissions.
* umount2: (libc)Mount-Unmount-Remount.
* umount: (libc)Mount-Unmount-Remount.
* uname: (libc)Platform Type.
* ungetc: (libc)How Unread.
* ungetwc: (libc)How Unread.
* unlink: (libc)Deleting Files.
* unlockpt: (libc)Allocation.
* unsetenv: (libc)Environment Access.
* updwtmp: (libc)Manipulating the Database.
* utime: (libc)File Times.
* utimes: (libc)File Times.
* utmpname: (libc)Manipulating the Database.
* utmpxname: (libc)XPG Functions.
* va_arg: (libc)Argument Macros.
* va_copy: (libc)Argument Macros.
* va_end: (libc)Argument Macros.
* va_start: (libc)Argument Macros.
* valloc: (libc)Aligned Memory Blocks.
* vasprintf: (libc)Variable Arguments Output.
* verr: (libc)Error Messages.
* verrx: (libc)Error Messages.
* versionsort64: (libc)Scanning Directory Content.
* versionsort: (libc)Scanning Directory Content.
* vfork: (libc)Creating a Process.
* vfprintf: (libc)Variable Arguments Output.
* vfscanf: (libc)Variable Arguments Input.
* vfwprintf: (libc)Variable Arguments Output.
* vfwscanf: (libc)Variable Arguments Input.
* vlimit: (libc)Limits on Resources.
* vprintf: (libc)Variable Arguments Output.
* vscanf: (libc)Variable Arguments Input.
* vsnprintf: (libc)Variable Arguments Output.
* vsprintf: (libc)Variable Arguments Output.
* vsscanf: (libc)Variable Arguments Input.
* vswprintf: (libc)Variable Arguments Output.
* vswscanf: (libc)Variable Arguments Input.
* vsyslog: (libc)syslog; vsyslog.
* vtimes: (libc)Resource Usage.
* vwarn: (libc)Error Messages.
* vwarnx: (libc)Error Messages.
* vwprintf: (libc)Variable Arguments Output.
* vwscanf: (libc)Variable Arguments Input.
* wait3: (libc)BSD Wait Functions.
* wait4: (libc)Process Completion.
* wait: (libc)Process Completion.
* waitpid: (libc)Process Completion.
* warn: (libc)Error Messages.
* warnx: (libc)Error Messages.
* wcpcpy: (libc)Copying and Concatenation.
* wcpncpy: (libc)Copying and Concatenation.
* wcrtomb: (libc)Converting a Character.
* wcscasecmp: (libc)String/Array Comparison.
* wcscat: (libc)Copying and Concatenation.
* wcschr: (libc)Search Functions.
* wcschrnul: (libc)Search Functions.
* wcscmp: (libc)String/Array Comparison.
* wcscoll: (libc)Collation Functions.
* wcscpy: (libc)Copying and Concatenation.
* wcscspn: (libc)Search Functions.
* wcsdup: (libc)Copying and Concatenation.
* wcsftime: (libc)Formatting Calendar Time.
* wcslen: (libc)String Length.
* wcsncasecmp: (libc)String/Array Comparison.
* wcsncat: (libc)Copying and Concatenation.
* wcsncmp: (libc)String/Array Comparison.
* wcsncpy: (libc)Copying and Concatenation.
* wcsnlen: (libc)String Length.
* wcsnrtombs: (libc)Converting Strings.
* wcspbrk: (libc)Search Functions.
* wcsrchr: (libc)Search Functions.
* wcsrtombs: (libc)Converting Strings.
* wcsspn: (libc)Search Functions.
* wcsstr: (libc)Search Functions.
* wcstod: (libc)Parsing of Floats.
* wcstof: (libc)Parsing of Floats.
* wcstoimax: (libc)Parsing of Integers.
* wcstok: (libc)Finding Tokens in a String.
* wcstol: (libc)Parsing of Integers.
* wcstold: (libc)Parsing of Floats.
* wcstoll: (libc)Parsing of Integers.
* wcstombs: (libc)Non-reentrant String Conversion.
* wcstoq: (libc)Parsing of Integers.
* wcstoul: (libc)Parsing of Integers.
* wcstoull: (libc)Parsing of Integers.
* wcstoumax: (libc)Parsing of Integers.
* wcstouq: (libc)Parsing of Integers.
* wcswcs: (libc)Search Functions.
* wcsxfrm: (libc)Collation Functions.
* wctob: (libc)Converting a Character.
* wctomb: (libc)Non-reentrant Character Conversion.
* wctrans: (libc)Wide Character Case Conversion.
* wctype: (libc)Classification of Wide Characters.
* wmemchr: (libc)Search Functions.
* wmemcmp: (libc)String/Array Comparison.
* wmemcpy: (libc)Copying and Concatenation.
* wmemmove: (libc)Copying and Concatenation.
* wmempcpy: (libc)Copying and Concatenation.
* wmemset: (libc)Copying and Concatenation.
* wordexp: (libc)Calling Wordexp.
* wordfree: (libc)Calling Wordexp.
* wprintf: (libc)Formatted Output Functions.
* write: (libc)I/O Primitives.
* writev: (libc)Scatter-Gather.
* wscanf: (libc)Formatted Input Functions.
* y0: (libc)Special Functions.
* y0f: (libc)Special Functions.
* y0l: (libc)Special Functions.
* y1: (libc)Special Functions.
* y1f: (libc)Special Functions.
* y1l: (libc)Special Functions.
* yn: (libc)Special Functions.
* ynf: (libc)Special Functions.
* ynl: (libc)Special Functions.
END-INFO-DIR-ENTRY

File: libc.info, Node: Canonical or Not, Next: Terminal Modes, Prev: I/O Queues, Up: Low-Level Terminal Interface
17.3 Two Styles of Input: Canonical or Not
==========================================
POSIX systems support two basic modes of input: canonical and
noncanonical.
In "canonical input processing" mode, terminal input is processed in
lines terminated by newline (''\n''), EOF, or EOL characters. No input
can be read until an entire line has been typed by the user, and the
'read' function (*note I/O Primitives::) returns at most a single line
of input, no matter how many bytes are requested.
In canonical input mode, the operating system provides input editing
facilities: some characters are interpreted specially to perform editing
operations within the current line of text, such as ERASE and KILL.
*Note Editing Characters::.
The constants '_POSIX_MAX_CANON' and 'MAX_CANON' parameterize the
maximum number of bytes which may appear in a single line of canonical
input. *Note Limits for Files::. You are guaranteed a maximum line
length of at least 'MAX_CANON' bytes, but the maximum might be larger,
and might even dynamically change size.
In "noncanonical input processing" mode, characters are not grouped
into lines, and ERASE and KILL processing is not performed. The
granularity with which bytes are read in noncanonical input mode is
controlled by the MIN and TIME settings. *Note Noncanonical Input::.
Most programs use canonical input mode, because this gives the user a
way to edit input line by line. The usual reason to use noncanonical
mode is when the program accepts single-character commands or provides
its own editing facilities.
The choice of canonical or noncanonical input is controlled by the
'ICANON' flag in the 'c_lflag' member of 'struct termios'. *Note Local
Modes::.

File: libc.info, Node: Terminal Modes, Next: BSD Terminal Modes, Prev: Canonical or Not, Up: Low-Level Terminal Interface
17.4 Terminal Modes
===================
This section describes the various terminal attributes that control how
input and output are done. The functions, data structures, and symbolic
constants are all declared in the header file 'termios.h'.
Don't confuse terminal attributes with file attributes. A device
special file which is associated with a terminal has file attributes as
described in *note File Attributes::. These are unrelated to the
attributes of the terminal device itself, which are discussed in this
section.
* Menu:
* Mode Data Types:: The data type 'struct termios' and
related types.
* Mode Functions:: Functions to read and set the terminal
attributes.
* Setting Modes:: The right way to set terminal attributes
reliably.
* Input Modes:: Flags controlling low-level input handling.
* Output Modes:: Flags controlling low-level output handling.
* Control Modes:: Flags controlling serial port behavior.
* Local Modes:: Flags controlling high-level input handling.
* Line Speed:: How to read and set the terminal line speed.
* Special Characters:: Characters that have special effects,
and how to change them.
* Noncanonical Input:: Controlling how long to wait for input.

File: libc.info, Node: Mode Data Types, Next: Mode Functions, Up: Terminal Modes
17.4.1 Terminal Mode Data Types
-------------------------------
The entire collection of attributes of a terminal is stored in a
structure of type 'struct termios'. This structure is used with the
functions 'tcgetattr' and 'tcsetattr' to read and set the attributes.
-- Data Type: struct termios
Structure that records all the I/O attributes of a terminal. The
structure includes at least the following members:
'tcflag_t c_iflag'
A bit mask specifying flags for input modes; see *note Input
Modes::.
'tcflag_t c_oflag'
A bit mask specifying flags for output modes; see *note Output
Modes::.
'tcflag_t c_cflag'
A bit mask specifying flags for control modes; see *note
Control Modes::.
'tcflag_t c_lflag'
A bit mask specifying flags for local modes; see *note Local
Modes::.
'cc_t c_cc[NCCS]'
An array specifying which characters are associated with
various control functions; see *note Special Characters::.
The 'struct termios' structure also contains members which encode
input and output transmission speeds, but the representation is not
specified. *Note Line Speed::, for how to examine and store the
speed values.
The following sections describe the details of the members of the
'struct termios' structure.
-- Data Type: tcflag_t
This is an unsigned integer type used to represent the various bit
masks for terminal flags.
-- Data Type: cc_t
This is an unsigned integer type used to represent characters
associated with various terminal control functions.
-- Macro: int NCCS
The value of this macro is the number of elements in the 'c_cc'
array.

File: libc.info, Node: Mode Functions, Next: Setting Modes, Prev: Mode Data Types, Up: Terminal Modes
17.4.2 Terminal Mode Functions
------------------------------
-- Function: int tcgetattr (int FILEDES, struct termios *TERMIOS-P)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function is used to examine the attributes of the terminal
device with file descriptor FILEDES. The attributes are returned
in the structure that TERMIOS-P points to.
If successful, 'tcgetattr' returns 0. A return value of -1
indicates an error. The following 'errno' error conditions are
defined for this function:
'EBADF'
The FILEDES argument is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal.
-- Function: int tcsetattr (int FILEDES, int WHEN, const struct termios
*TERMIOS-P)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function sets the attributes of the terminal device with file
descriptor FILEDES. The new attributes are taken from the
structure that TERMIOS-P points to.
The WHEN argument specifies how to deal with input and output
already queued. It can be one of the following values:
'TCSANOW'
Make the change immediately.
'TCSADRAIN'
Make the change after waiting until all queued output has been
written. You should usually use this option when changing
parameters that affect output.
'TCSAFLUSH'
This is like 'TCSADRAIN', but also discards any queued input.
'TCSASOFT'
This is a flag bit that you can add to any of the above
alternatives. Its meaning is to inhibit alteration of the
state of the terminal hardware. It is a BSD extension; it is
only supported on BSD systems and GNU/Hurd systems.
Using 'TCSASOFT' is exactly the same as setting the 'CIGNORE'
bit in the 'c_cflag' member of the structure TERMIOS-P points
to. *Note Control Modes::, for a description of 'CIGNORE'.
If this function is called from a background process on its
controlling terminal, normally all processes in the process group
are sent a 'SIGTTOU' signal, in the same way as if the process were
trying to write to the terminal. The exception is if the calling
process itself is ignoring or blocking 'SIGTTOU' signals, in which
case the operation is performed and no signal is sent. *Note Job
Control::.
If successful, 'tcsetattr' returns 0. A return value of -1
indicates an error. The following 'errno' error conditions are
defined for this function:
'EBADF'
The FILEDES argument is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal.
'EINVAL'
Either the value of the 'when' argument is not valid, or there
is something wrong with the data in the TERMIOS-P argument.
Although 'tcgetattr' and 'tcsetattr' specify the terminal device with
a file descriptor, the attributes are those of the terminal device
itself and not of the file descriptor. This means that the effects of
changing terminal attributes are persistent; if another process opens
the terminal file later on, it will see the changed attributes even
though it doesn't have anything to do with the open file descriptor you
originally specified in changing the attributes.
Similarly, if a single process has multiple or duplicated file
descriptors for the same terminal device, changing the terminal
attributes affects input and output to all of these file descriptors.
This means, for example, that you can't open one file descriptor or
stream to read from a terminal in the normal line-buffered, echoed mode;
and simultaneously have another file descriptor for the same terminal
that you use to read from it in single-character, non-echoed mode.
Instead, you have to explicitly switch the terminal back and forth
between the two modes.

File: libc.info, Node: Setting Modes, Next: Input Modes, Prev: Mode Functions, Up: Terminal Modes
17.4.3 Setting Terminal Modes Properly
--------------------------------------
When you set terminal modes, you should call 'tcgetattr' first to get
the current modes of the particular terminal device, modify only those
modes that you are really interested in, and store the result with
'tcsetattr'.
It's a bad idea to simply initialize a 'struct termios' structure to
a chosen set of attributes and pass it directly to 'tcsetattr'. Your
program may be run years from now, on systems that support members not
documented in this manual. The way to avoid setting these members to
unreasonable values is to avoid changing them.
What's more, different terminal devices may require different mode
settings in order to function properly. So you should avoid blindly
copying attributes from one terminal device to another.
When a member contains a collection of independent flags, as the
'c_iflag', 'c_oflag' and 'c_cflag' members do, even setting the entire
member is a bad idea, because particular operating systems have their
own flags. Instead, you should start with the current value of the
member and alter only the flags whose values matter in your program,
leaving any other flags unchanged.
Here is an example of how to set one flag ('ISTRIP') in the 'struct
termios' structure while properly preserving all the other data in the
structure:
int
set_istrip (int desc, int value)
{
struct termios settings;
int result;
result = tcgetattr (desc, &settings);
if (result < 0)
{
perror ("error in tcgetattr");
return 0;
}
settings.c_iflag &= ~ISTRIP;
if (value)
settings.c_iflag |= ISTRIP;
result = tcsetattr (desc, TCSANOW, &settings);
if (result < 0)
{
perror ("error in tcsetattr");
return 0;
}
return 1;
}

File: libc.info, Node: Input Modes, Next: Output Modes, Prev: Setting Modes, Up: Terminal Modes
17.4.4 Input Modes
------------------
This section describes the terminal attribute flags that control fairly
low-level aspects of input processing: handling of parity errors, break
signals, flow control, and <RET> and <LFD> characters.
All of these flags are bits in the 'c_iflag' member of the 'struct
termios' structure. The member is an integer, and you change flags
using the operators '&', '|' and '^'. Don't try to specify the entire
value for 'c_iflag'--instead, change only specific flags and leave the
rest untouched (*note Setting Modes::).
-- Macro: tcflag_t INPCK
If this bit is set, input parity checking is enabled. If it is not
set, no checking at all is done for parity errors on input; the
characters are simply passed through to the application.
Parity checking on input processing is independent of whether
parity detection and generation on the underlying terminal hardware
is enabled; see *note Control Modes::. For example, you could
clear the 'INPCK' input mode flag and set the 'PARENB' control mode
flag to ignore parity errors on input, but still generate parity on
output.
If this bit is set, what happens when a parity error is detected
depends on whether the 'IGNPAR' or 'PARMRK' bits are set. If
neither of these bits are set, a byte with a parity error is passed
to the application as a ''\0'' character.
-- Macro: tcflag_t IGNPAR
If this bit is set, any byte with a framing or parity error is
ignored. This is only useful if 'INPCK' is also set.
-- Macro: tcflag_t PARMRK
If this bit is set, input bytes with parity or framing errors are
marked when passed to the program. This bit is meaningful only
when 'INPCK' is set and 'IGNPAR' is not set.
The way erroneous bytes are marked is with two preceding bytes,
'377' and '0'. Thus, the program actually reads three bytes for
one erroneous byte received from the terminal.
If a valid byte has the value '0377', and 'ISTRIP' (see below) is
not set, the program might confuse it with the prefix that marks a
parity error. So a valid byte '0377' is passed to the program as
two bytes, '0377' '0377', in this case.
-- Macro: tcflag_t ISTRIP
If this bit is set, valid input bytes are stripped to seven bits;
otherwise, all eight bits are available for programs to read.
-- Macro: tcflag_t IGNBRK
If this bit is set, break conditions are ignored.
A "break condition" is defined in the context of asynchronous
serial data transmission as a series of zero-value bits longer than
a single byte.
-- Macro: tcflag_t BRKINT
If this bit is set and 'IGNBRK' is not set, a break condition
clears the terminal input and output queues and raises a 'SIGINT'
signal for the foreground process group associated with the
terminal.
If neither 'BRKINT' nor 'IGNBRK' are set, a break condition is
passed to the application as a single ''\0'' character if 'PARMRK'
is not set, or otherwise as a three-character sequence ''\377'',
''\0'', ''\0''.
-- Macro: tcflag_t IGNCR
If this bit is set, carriage return characters (''\r'') are
discarded on input. Discarding carriage return may be useful on
terminals that send both carriage return and linefeed when you type
the <RET> key.
-- Macro: tcflag_t ICRNL
If this bit is set and 'IGNCR' is not set, carriage return
characters (''\r'') received as input are passed to the application
as newline characters (''\n'').
-- Macro: tcflag_t INLCR
If this bit is set, newline characters (''\n'') received as input
are passed to the application as carriage return characters
(''\r'').
-- Macro: tcflag_t IXOFF
If this bit is set, start/stop control on input is enabled. In
other words, the computer sends STOP and START characters as
necessary to prevent input from coming in faster than programs are
reading it. The idea is that the actual terminal hardware that is
generating the input data responds to a STOP character by
suspending transmission, and to a START character by resuming
transmission. *Note Start/Stop Characters::.
-- Macro: tcflag_t IXON
If this bit is set, start/stop control on output is enabled. In
other words, if the computer receives a STOP character, it suspends
output until a START character is received. In this case, the STOP
and START characters are never passed to the application program.
If this bit is not set, then START and STOP can be read as ordinary
characters. *Note Start/Stop Characters::.
-- Macro: tcflag_t IXANY
If this bit is set, any input character restarts output when output
has been suspended with the STOP character. Otherwise, only the
START character restarts output.
This is a BSD extension; it exists only on BSD systems and
GNU/Linux and GNU/Hurd systems.
-- Macro: tcflag_t IMAXBEL
If this bit is set, then filling up the terminal input buffer sends
a BEL character (code '007') to the terminal to ring the bell.
This is a BSD extension.

File: libc.info, Node: Output Modes, Next: Control Modes, Prev: Input Modes, Up: Terminal Modes
17.4.5 Output Modes
-------------------
This section describes the terminal flags and fields that control how
output characters are translated and padded for display. All of these
are contained in the 'c_oflag' member of the 'struct termios' structure.
The 'c_oflag' member itself is an integer, and you change the flags
and fields using the operators '&', '|', and '^'. Don't try to specify
the entire value for 'c_oflag'--instead, change only specific flags and
leave the rest untouched (*note Setting Modes::).
-- Macro: tcflag_t OPOST
If this bit is set, output data is processed in some unspecified
way so that it is displayed appropriately on the terminal device.
This typically includes mapping newline characters (''\n'') onto
carriage return and linefeed pairs.
If this bit isn't set, the characters are transmitted as-is.
The following three bits are effective only if 'OPOST' is set.
-- Macro: tcflag_t ONLCR
If this bit is set, convert the newline character on output into a
pair of characters, carriage return followed by linefeed.
-- Macro: tcflag_t OXTABS
If this bit is set, convert tab characters on output into the
appropriate number of spaces to emulate a tab stop every eight
columns. This bit exists only on BSD systems and GNU/Hurd systems;
on GNU/Linux systems it is available as 'XTABS'.
-- Macro: tcflag_t ONOEOT
If this bit is set, discard 'C-d' characters (code '004') on
output. These characters cause many dial-up terminals to
disconnect. This bit exists only on BSD systems and GNU/Hurd
systems.

File: libc.info, Node: Control Modes, Next: Local Modes, Prev: Output Modes, Up: Terminal Modes
17.4.6 Control Modes
--------------------
This section describes the terminal flags and fields that control
parameters usually associated with asynchronous serial data
transmission. These flags may not make sense for other kinds of
terminal ports (such as a network connection pseudo-terminal). All of
these are contained in the 'c_cflag' member of the 'struct termios'
structure.
The 'c_cflag' member itself is an integer, and you change the flags
and fields using the operators '&', '|', and '^'. Don't try to specify
the entire value for 'c_cflag'--instead, change only specific flags and
leave the rest untouched (*note Setting Modes::).
-- Macro: tcflag_t CLOCAL
If this bit is set, it indicates that the terminal is connected
"locally" and that the modem status lines (such as carrier detect)
should be ignored.
On many systems if this bit is not set and you call 'open' without
the 'O_NONBLOCK' flag set, 'open' blocks until a modem connection
is established.
If this bit is not set and a modem disconnect is detected, a
'SIGHUP' signal is sent to the controlling process group for the
terminal (if it has one). Normally, this causes the process to
exit; see *note Signal Handling::. Reading from the terminal after
a disconnect causes an end-of-file condition, and writing causes an
'EIO' error to be returned. The terminal device must be closed and
reopened to clear the condition.
-- Macro: tcflag_t HUPCL
If this bit is set, a modem disconnect is generated when all
processes that have the terminal device open have either closed the
file or exited.
-- Macro: tcflag_t CREAD
If this bit is set, input can be read from the terminal.
Otherwise, input is discarded when it arrives.
-- Macro: tcflag_t CSTOPB
If this bit is set, two stop bits are used. Otherwise, only one
stop bit is used.
-- Macro: tcflag_t PARENB
If this bit is set, generation and detection of a parity bit are
enabled. *Note Input Modes::, for information on how input parity
errors are handled.
If this bit is not set, no parity bit is added to output
characters, and input characters are not checked for correct
parity.
-- Macro: tcflag_t PARODD
This bit is only useful if 'PARENB' is set. If 'PARODD' is set,
odd parity is used, otherwise even parity is used.
The control mode flags also includes a field for the number of bits
per character. You can use the 'CSIZE' macro as a mask to extract the
value, like this: 'settings.c_cflag & CSIZE'.
-- Macro: tcflag_t CSIZE
This is a mask for the number of bits per character.
-- Macro: tcflag_t CS5
This specifies five bits per byte.
-- Macro: tcflag_t CS6
This specifies six bits per byte.
-- Macro: tcflag_t CS7
This specifies seven bits per byte.
-- Macro: tcflag_t CS8
This specifies eight bits per byte.
The following four bits are BSD extensions; these exist only on BSD
systems and GNU/Hurd systems.
-- Macro: tcflag_t CCTS_OFLOW
If this bit is set, enable flow control of output based on the CTS
wire (RS232 protocol).
-- Macro: tcflag_t CRTS_IFLOW
If this bit is set, enable flow control of input based on the RTS
wire (RS232 protocol).
-- Macro: tcflag_t MDMBUF
If this bit is set, enable carrier-based flow control of output.
-- Macro: tcflag_t CIGNORE
If this bit is set, it says to ignore the control modes and line
speed values entirely. This is only meaningful in a call to
'tcsetattr'.
The 'c_cflag' member and the line speed values returned by
'cfgetispeed' and 'cfgetospeed' will be unaffected by the call.
'CIGNORE' is useful if you want to set all the software modes in
the other members, but leave the hardware details in 'c_cflag'
unchanged. (This is how the 'TCSASOFT' flag to 'tcsettattr'
works.)
This bit is never set in the structure filled in by 'tcgetattr'.

File: libc.info, Node: Local Modes, Next: Line Speed, Prev: Control Modes, Up: Terminal Modes
17.4.7 Local Modes
------------------
This section describes the flags for the 'c_lflag' member of the 'struct
termios' structure. These flags generally control higher-level aspects
of input processing than the input modes flags described in *note Input
Modes::, such as echoing, signals, and the choice of canonical or
noncanonical input.
The 'c_lflag' member itself is an integer, and you change the flags
and fields using the operators '&', '|', and '^'. Don't try to specify
the entire value for 'c_lflag'--instead, change only specific flags and
leave the rest untouched (*note Setting Modes::).
-- Macro: tcflag_t ICANON
This bit, if set, enables canonical input processing mode.
Otherwise, input is processed in noncanonical mode. *Note
Canonical or Not::.
-- Macro: tcflag_t ECHO
If this bit is set, echoing of input characters back to the
terminal is enabled.
-- Macro: tcflag_t ECHOE
If this bit is set, echoing indicates erasure of input with the
ERASE character by erasing the last character in the current line
from the screen. Otherwise, the character erased is re-echoed to
show what has happened (suitable for a printing terminal).
This bit only controls the display behavior; the 'ICANON' bit by
itself controls actual recognition of the ERASE character and
erasure of input, without which 'ECHOE' is simply irrelevant.
-- Macro: tcflag_t ECHOPRT
This bit is like 'ECHOE', enables display of the ERASE character in
a way that is geared to a hardcopy terminal. When you type the
ERASE character, a '\' character is printed followed by the first
character erased. Typing the ERASE character again just prints the
next character erased. Then, the next time you type a normal
character, a '/' character is printed before the character echoes.
This is a BSD extension, and exists only in BSD systems and
GNU/Linux and GNU/Hurd systems.
-- Macro: tcflag_t ECHOK
This bit enables special display of the KILL character by moving to
a new line after echoing the KILL character normally. The behavior
of 'ECHOKE' (below) is nicer to look at.
If this bit is not set, the KILL character echoes just as it would
if it were not the KILL character. Then it is up to the user to
remember that the KILL character has erased the preceding input;
there is no indication of this on the screen.
This bit only controls the display behavior; the 'ICANON' bit by
itself controls actual recognition of the KILL character and
erasure of input, without which 'ECHOK' is simply irrelevant.
-- Macro: tcflag_t ECHOKE
This bit is similar to 'ECHOK'. It enables special display of the
KILL character by erasing on the screen the entire line that has
been killed. This is a BSD extension, and exists only in BSD
systems and GNU/Linux and GNU/Hurd systems.
-- Macro: tcflag_t ECHONL
If this bit is set and the 'ICANON' bit is also set, then the
newline (''\n'') character is echoed even if the 'ECHO' bit is not
set.
-- Macro: tcflag_t ECHOCTL
If this bit is set and the 'ECHO' bit is also set, echo control
characters with '^' followed by the corresponding text character.
Thus, control-A echoes as '^A'. This is usually the preferred mode
for interactive input, because echoing a control character back to
the terminal could have some undesired effect on the terminal.
This is a BSD extension, and exists only in BSD systems and
GNU/Linux and GNU/Hurd systems.
-- Macro: tcflag_t ISIG
This bit controls whether the INTR, QUIT, and SUSP characters are
recognized. The functions associated with these characters are
performed if and only if this bit is set. Being in canonical or
noncanonical input mode has no affect on the interpretation of
these characters.
You should use caution when disabling recognition of these
characters. Programs that cannot be interrupted interactively are
very user-unfriendly. If you clear this bit, your program should
provide some alternate interface that allows the user to
interactively send the signals associated with these characters, or
to escape from the program.
*Note Signal Characters::.
-- Macro: tcflag_t IEXTEN
POSIX.1 gives 'IEXTEN' implementation-defined meaning, so you
cannot rely on this interpretation on all systems.
On BSD systems and GNU/Linux and GNU/Hurd systems, it enables the
LNEXT and DISCARD characters. *Note Other Special::.
-- Macro: tcflag_t NOFLSH
Normally, the INTR, QUIT, and SUSP characters cause input and
output queues for the terminal to be cleared. If this bit is set,
the queues are not cleared.
-- Macro: tcflag_t TOSTOP
If this bit is set and the system supports job control, then
'SIGTTOU' signals are generated by background processes that
attempt to write to the terminal. *Note Access to the Terminal::.
The following bits are BSD extensions; they exist only on BSD systems
and GNU/Hurd systems.
-- Macro: tcflag_t ALTWERASE
This bit determines how far the WERASE character should erase. The
WERASE character erases back to the beginning of a word; the
question is, where do words begin?
If this bit is clear, then the beginning of a word is a
nonwhitespace character following a whitespace character. If the
bit is set, then the beginning of a word is an alphanumeric
character or underscore following a character which is none of
those.
*Note Editing Characters::, for more information about the WERASE
character.
-- Macro: tcflag_t FLUSHO
This is the bit that toggles when the user types the DISCARD
character. While this bit is set, all output is discarded. *Note
Other Special::.
-- Macro: tcflag_t NOKERNINFO
Setting this bit disables handling of the STATUS character. *Note
Other Special::.
-- Macro: tcflag_t PENDIN
If this bit is set, it indicates that there is a line of input that
needs to be reprinted. Typing the REPRINT character sets this bit;
the bit remains set until reprinting is finished. *Note Editing
Characters::.

File: libc.info, Node: Line Speed, Next: Special Characters, Prev: Local Modes, Up: Terminal Modes
17.4.8 Line Speed
-----------------
The terminal line speed tells the computer how fast to read and write
data on the terminal.
If the terminal is connected to a real serial line, the terminal
speed you specify actually controls the line--if it doesn't match the
terminal's own idea of the speed, communication does not work. Real
serial ports accept only certain standard speeds. Also, particular
hardware may not support even all the standard speeds. Specifying a
speed of zero hangs up a dialup connection and turns off modem control
signals.
If the terminal is not a real serial line (for example, if it is a
network connection), then the line speed won't really affect data
transmission speed, but some programs will use it to determine the
amount of padding needed. It's best to specify a line speed value that
matches the actual speed of the actual terminal, but you can safely
experiment with different values to vary the amount of padding.
There are actually two line speeds for each terminal, one for input
and one for output. You can set them independently, but most often
terminals use the same speed for both directions.
The speed values are stored in the 'struct termios' structure, but
don't try to access them in the 'struct termios' structure directly.
Instead, you should use the following functions to read and store them:
-- Function: speed_t cfgetospeed (const struct termios *TERMIOS-P)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function returns the output line speed stored in the structure
'*TERMIOS-P'.
-- Function: speed_t cfgetispeed (const struct termios *TERMIOS-P)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function returns the input line speed stored in the structure
'*TERMIOS-P'.
-- Function: int cfsetospeed (struct termios *TERMIOS-P, speed_t SPEED)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function stores SPEED in '*TERMIOS-P' as the output speed.
The normal return value is 0; a value of -1 indicates an error. If
SPEED is not a speed, 'cfsetospeed' returns -1.
-- Function: int cfsetispeed (struct termios *TERMIOS-P, speed_t SPEED)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function stores SPEED in '*TERMIOS-P' as the input speed. The
normal return value is 0; a value of -1 indicates an error. If
SPEED is not a speed, 'cfsetospeed' returns -1.
-- Function: int cfsetspeed (struct termios *TERMIOS-P, speed_t SPEED)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function stores SPEED in '*TERMIOS-P' as both the input and
output speeds. The normal return value is 0; a value of -1
indicates an error. If SPEED is not a speed, 'cfsetspeed' returns
-1. This function is an extension in 4.4 BSD.
-- Data Type: speed_t
The 'speed_t' type is an unsigned integer data type used to
represent line speeds.
The functions 'cfsetospeed' and 'cfsetispeed' report errors only for
speed values that the system simply cannot handle. If you specify a
speed value that is basically acceptable, then those functions will
succeed. But they do not check that a particular hardware device can
actually support the specified speeds--in fact, they don't know which
device you plan to set the speed for. If you use 'tcsetattr' to set the
speed of a particular device to a value that it cannot handle,
'tcsetattr' returns -1.
*Portability note:* In the GNU C Library, the functions above accept
speeds measured in bits per second as input, and return speed values
measured in bits per second. Other libraries require speeds to be
indicated by special codes. For POSIX.1 portability, you must use one
of the following symbols to represent the speed; their precise numeric
values are system-dependent, but each name has a fixed meaning: 'B110'
stands for 110 bps, 'B300' for 300 bps, and so on. There is no portable
way to represent any speed but these, but these are the only speeds that
typical serial lines can support.
B0 B50 B75 B110 B134 B150 B200
B300 B600 B1200 B1800 B2400 B4800
B9600 B19200 B38400 B57600 B115200
B230400 B460800
BSD defines two additional speed symbols as aliases: 'EXTA' is an
alias for 'B19200' and 'EXTB' is an alias for 'B38400'. These aliases
are obsolete.

File: libc.info, Node: Special Characters, Next: Noncanonical Input, Prev: Line Speed, Up: Terminal Modes
17.4.9 Special Characters
-------------------------
In canonical input, the terminal driver recognizes a number of special
characters which perform various control functions. These include the
ERASE character (usually <DEL>) for editing input, and other editing
characters. The INTR character (normally 'C-c') for sending a 'SIGINT'
signal, and other signal-raising characters, may be available in either
canonical or noncanonical input mode. All these characters are
described in this section.
The particular characters used are specified in the 'c_cc' member of
the 'struct termios' structure. This member is an array; each element
specifies the character for a particular role. Each element has a
symbolic constant that stands for the index of that element--for
example, 'VINTR' is the index of the element that specifies the INTR
character, so storing ''='' in 'TERMIOS.c_cc[VINTR]' specifies '=' as
the INTR character.
On some systems, you can disable a particular special character
function by specifying the value '_POSIX_VDISABLE' for that role. This
value is unequal to any possible character code. *Note Options for
Files::, for more information about how to tell whether the operating
system you are using supports '_POSIX_VDISABLE'.
* Menu:
* Editing Characters:: Special characters that terminate lines and
delete text, and other editing functions.
* Signal Characters:: Special characters that send or raise signals
to or for certain classes of processes.
* Start/Stop Characters:: Special characters that suspend or resume
suspended output.
* Other Special:: Other special characters for BSD systems:
they can discard output, and print status.

File: libc.info, Node: Editing Characters, Next: Signal Characters, Up: Special Characters
17.4.9.1 Characters for Input Editing
.....................................
These special characters are active only in canonical input mode. *Note
Canonical or Not::.
-- Macro: int VEOF
This is the subscript for the EOF character in the special control
character array. 'TERMIOS.c_cc[VEOF]' holds the character itself.
The EOF character is recognized only in canonical input mode. It
acts as a line terminator in the same way as a newline character,
but if the EOF character is typed at the beginning of a line it
causes 'read' to return a byte count of zero, indicating
end-of-file. The EOF character itself is discarded.
Usually, the EOF character is 'C-d'.
-- Macro: int VEOL
This is the subscript for the EOL character in the special control
character array. 'TERMIOS.c_cc[VEOL]' holds the character itself.
The EOL character is recognized only in canonical input mode. It
acts as a line terminator, just like a newline character. The EOL
character is not discarded; it is read as the last character in the
input line.
You don't need to use the EOL character to make <RET> end a line.
Just set the ICRNL flag. In fact, this is the default state of
affairs.
-- Macro: int VEOL2
This is the subscript for the EOL2 character in the special control
character array. 'TERMIOS.c_cc[VEOL2]' holds the character itself.
The EOL2 character works just like the EOL character (see above),
but it can be a different character. Thus, you can specify two
characters to terminate an input line, by setting EOL to one of
them and EOL2 to the other.
The EOL2 character is a BSD extension; it exists only on BSD
systems and GNU/Linux and GNU/Hurd systems.
-- Macro: int VERASE
This is the subscript for the ERASE character in the special
control character array. 'TERMIOS.c_cc[VERASE]' holds the
character itself.
The ERASE character is recognized only in canonical input mode.
When the user types the erase character, the previous character
typed is discarded. (If the terminal generates multibyte character
sequences, this may cause more than one byte of input to be
discarded.) This cannot be used to erase past the beginning of the
current line of text. The ERASE character itself is discarded.
Usually, the ERASE character is <DEL>.
-- Macro: int VWERASE
This is the subscript for the WERASE character in the special
control character array. 'TERMIOS.c_cc[VWERASE]' holds the
character itself.
The WERASE character is recognized only in canonical mode. It
erases an entire word of prior input, and any whitespace after it;
whitespace characters before the word are not erased.
The definition of a "word" depends on the setting of the
'ALTWERASE' mode; *note Local Modes::.
If the 'ALTWERASE' mode is not set, a word is defined as a sequence
of any characters except space or tab.
If the 'ALTWERASE' mode is set, a word is defined as a sequence of
characters containing only letters, numbers, and underscores,
optionally followed by one character that is not a letter, number,
or underscore.
The WERASE character is usually 'C-w'.
This is a BSD extension.
-- Macro: int VKILL
This is the subscript for the KILL character in the special control
character array. 'TERMIOS.c_cc[VKILL]' holds the character itself.
The KILL character is recognized only in canonical input mode.
When the user types the kill character, the entire contents of the
current line of input are discarded. The kill character itself is
discarded too.
The KILL character is usually 'C-u'.
-- Macro: int VREPRINT
This is the subscript for the REPRINT character in the special
control character array. 'TERMIOS.c_cc[VREPRINT]' holds the
character itself.
The REPRINT character is recognized only in canonical mode. It
reprints the current input line. If some asynchronous output has
come while you are typing, this lets you see the line you are
typing clearly again.
The REPRINT character is usually 'C-r'.
This is a BSD extension.

File: libc.info, Node: Signal Characters, Next: Start/Stop Characters, Prev: Editing Characters, Up: Special Characters
17.4.9.2 Characters that Cause Signals
......................................
These special characters may be active in either canonical or
noncanonical input mode, but only when the 'ISIG' flag is set (*note
Local Modes::).
-- Macro: int VINTR
This is the subscript for the INTR character in the special control
character array. 'TERMIOS.c_cc[VINTR]' holds the character itself.
The INTR (interrupt) character raises a 'SIGINT' signal for all
processes in the foreground job associated with the terminal. The
INTR character itself is then discarded. *Note Signal Handling::,
for more information about signals.
Typically, the INTR character is 'C-c'.
-- Macro: int VQUIT
This is the subscript for the QUIT character in the special control
character array. 'TERMIOS.c_cc[VQUIT]' holds the character itself.
The QUIT character raises a 'SIGQUIT' signal for all processes in
the foreground job associated with the terminal. The QUIT
character itself is then discarded. *Note Signal Handling::, for
more information about signals.
Typically, the QUIT character is 'C-\'.
-- Macro: int VSUSP
This is the subscript for the SUSP character in the special control
character array. 'TERMIOS.c_cc[VSUSP]' holds the character itself.
The SUSP (suspend) character is recognized only if the
implementation supports job control (*note Job Control::). It
causes a 'SIGTSTP' signal to be sent to all processes in the
foreground job associated with the terminal. The SUSP character
itself is then discarded. *Note Signal Handling::, for more
information about signals.
Typically, the SUSP character is 'C-z'.
Few applications disable the normal interpretation of the SUSP
character. If your program does this, it should provide some other
mechanism for the user to stop the job. When the user invokes this
mechanism, the program should send a 'SIGTSTP' signal to the process
group of the process, not just to the process itself. *Note Signaling
Another Process::.
-- Macro: int VDSUSP
This is the subscript for the DSUSP character in the special
control character array. 'TERMIOS.c_cc[VDSUSP]' holds the
character itself.
The DSUSP (suspend) character is recognized only if the
implementation supports job control (*note Job Control::). It
sends a 'SIGTSTP' signal, like the SUSP character, but not right
away--only when the program tries to read it as input. Not all
systems with job control support DSUSP; only BSD-compatible systems
(including GNU/Hurd systems).
*Note Signal Handling::, for more information about signals.
Typically, the DSUSP character is 'C-y'.

File: libc.info, Node: Start/Stop Characters, Next: Other Special, Prev: Signal Characters, Up: Special Characters
17.4.9.3 Special Characters for Flow Control
............................................
These special characters may be active in either canonical or
noncanonical input mode, but their use is controlled by the flags 'IXON'
and 'IXOFF' (*note Input Modes::).
-- Macro: int VSTART
This is the subscript for the START character in the special
control character array. 'TERMIOS.c_cc[VSTART]' holds the
character itself.
The START character is used to support the 'IXON' and 'IXOFF' input
modes. If 'IXON' is set, receiving a START character resumes
suspended output; the START character itself is discarded. If
'IXANY' is set, receiving any character at all resumes suspended
output; the resuming character is not discarded unless it is the
START character. 'IXOFF' is set, the system may also transmit
START characters to the terminal.
The usual value for the START character is 'C-q'. You may not be
able to change this value--the hardware may insist on using 'C-q'
regardless of what you specify.
-- Macro: int VSTOP
This is the subscript for the STOP character in the special control
character array. 'TERMIOS.c_cc[VSTOP]' holds the character itself.
The STOP character is used to support the 'IXON' and 'IXOFF' input
modes. If 'IXON' is set, receiving a STOP character causes output
to be suspended; the STOP character itself is discarded. If
'IXOFF' is set, the system may also transmit STOP characters to the
terminal, to prevent the input queue from overflowing.
The usual value for the STOP character is 'C-s'. You may not be
able to change this value--the hardware may insist on using 'C-s'
regardless of what you specify.

File: libc.info, Node: Other Special, Prev: Start/Stop Characters, Up: Special Characters
17.4.9.4 Other Special Characters
.................................
-- Macro: int VLNEXT
This is the subscript for the LNEXT character in the special
control character array. 'TERMIOS.c_cc[VLNEXT]' holds the
character itself.
The LNEXT character is recognized only when 'IEXTEN' is set, but in
both canonical and noncanonical mode. It disables any special
significance of the next character the user types. Even if the
character would normally perform some editing function or generate
a signal, it is read as a plain character. This is the analogue of
the 'C-q' command in Emacs. "LNEXT" stands for "literal next."
The LNEXT character is usually 'C-v'.
This character is available on BSD systems and GNU/Linux and
GNU/Hurd systems.
-- Macro: int VDISCARD
This is the subscript for the DISCARD character in the special
control character array. 'TERMIOS.c_cc[VDISCARD]' holds the
character itself.
The DISCARD character is recognized only when 'IEXTEN' is set, but
in both canonical and noncanonical mode. Its effect is to toggle
the discard-output flag. When this flag is set, all program output
is discarded. Setting the flag also discards all output currently
in the output buffer. Typing any other character resets the flag.
This character is available on BSD systems and GNU/Linux and
GNU/Hurd systems.
-- Macro: int VSTATUS
This is the subscript for the STATUS character in the special
control character array. 'TERMIOS.c_cc[VSTATUS]' holds the
character itself.
The STATUS character's effect is to print out a status message
about how the current process is running.
The STATUS character is recognized only in canonical mode, and only
if 'NOKERNINFO' is not set.
This character is available only on BSD systems and GNU/Hurd
systems.

File: libc.info, Node: Noncanonical Input, Prev: Special Characters, Up: Terminal Modes
17.4.10 Noncanonical Input
--------------------------
In noncanonical input mode, the special editing characters such as ERASE
and KILL are ignored. The system facilities for the user to edit input
are disabled in noncanonical mode, so that all input characters (unless
they are special for signal or flow-control purposes) are passed to the
application program exactly as typed. It is up to the application
program to give the user ways to edit the input, if appropriate.
Noncanonical mode offers special parameters called MIN and TIME for
controlling whether and how long to wait for input to be available. You
can even use them to avoid ever waiting--to return immediately with
whatever input is available, or with no input.
The MIN and TIME are stored in elements of the 'c_cc' array, which is
a member of the 'struct termios' structure. Each element of this array
has a particular role, and each element has a symbolic constant that
stands for the index of that element. 'VMIN' and 'VMAX' are the names
for the indices in the array of the MIN and TIME slots.
-- Macro: int VMIN
This is the subscript for the MIN slot in the 'c_cc' array. Thus,
'TERMIOS.c_cc[VMIN]' is the value itself.
The MIN slot is only meaningful in noncanonical input mode; it
specifies the minimum number of bytes that must be available in the
input queue in order for 'read' to return.
-- Macro: int VTIME
This is the subscript for the TIME slot in the 'c_cc' array. Thus,
'TERMIOS.c_cc[VTIME]' is the value itself.
The TIME slot is only meaningful in noncanonical input mode; it
specifies how long to wait for input before returning, in units of
0.1 seconds.
The MIN and TIME values interact to determine the criterion for when
'read' should return; their precise meanings depend on which of them are
nonzero. There are four possible cases:
* Both TIME and MIN are nonzero.
In this case, TIME specifies how long to wait after each input
character to see if more input arrives. After the first character
received, 'read' keeps waiting until either MIN bytes have arrived
in all, or TIME elapses with no further input.
'read' always blocks until the first character arrives, even if
TIME elapses first. 'read' can return more than MIN characters if
more than MIN happen to be in the queue.
* Both MIN and TIME are zero.
In this case, 'read' always returns immediately with as many
characters as are available in the queue, up to the number
requested. If no input is immediately available, 'read' returns a
value of zero.
* MIN is zero but TIME has a nonzero value.
In this case, 'read' waits for time TIME for input to become
available; the availability of a single byte is enough to satisfy
the read request and cause 'read' to return. When it returns, it
returns as many characters as are available, up to the number
requested. If no input is available before the timer expires,
'read' returns a value of zero.
* TIME is zero but MIN has a nonzero value.
In this case, 'read' waits until at least MIN bytes are available
in the queue. At that time, 'read' returns as many characters as
are available, up to the number requested. 'read' can return more
than MIN characters if more than MIN happen to be in the queue.
What happens if MIN is 50 and you ask to read just 10 bytes?
Normally, 'read' waits until there are 50 bytes in the buffer (or, more
generally, the wait condition described above is satisfied), and then
reads 10 of them, leaving the other 40 buffered in the operating system
for a subsequent call to 'read'.
*Portability note:* On some systems, the MIN and TIME slots are
actually the same as the EOF and EOL slots. This causes no serious
problem because the MIN and TIME slots are used only in noncanonical
input and the EOF and EOL slots are used only in canonical input, but it
isn't very clean. The GNU C Library allocates separate slots for these
uses.
-- Function: void cfmakeraw (struct termios *TERMIOS-P)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function provides an easy way to set up '*TERMIOS-P' for what
has traditionally been called "raw mode" in BSD. This uses
noncanonical input, and turns off most processing to give an
unmodified channel to the terminal.
It does exactly this:
TERMIOS-P->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
|INLCR|IGNCR|ICRNL|IXON);
TERMIOS-P->c_oflag &= ~OPOST;
TERMIOS-P->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
TERMIOS-P->c_cflag &= ~(CSIZE|PARENB);
TERMIOS-P->c_cflag |= CS8;

File: libc.info, Node: BSD Terminal Modes, Next: Line Control, Prev: Terminal Modes, Up: Low-Level Terminal Interface
17.5 BSD Terminal Modes
=======================
The usual way to get and set terminal modes is with the functions
described in *note Terminal Modes::. However, on some systems you can
use the BSD-derived functions in this section to do some of the same
thing. On many systems, these functions do not exist. Even with the
GNU C Library, the functions simply fail with 'errno' = 'ENOSYS' with
many kernels, including Linux.
The symbols used in this section are declared in 'sgtty.h'.
-- Data Type: struct sgttyb
This structure is an input or output parameter list for 'gtty' and
'stty'.
'char sg_ispeed'
Line speed for input
'char sg_ospeed'
Line speed for output
'char sg_erase'
Erase character
'char sg_kill'
Kill character
'int sg_flags'
Various flags
-- Function: int gtty (int FILEDES, struct sgttyb *ATTRIBUTES)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function gets the attributes of a terminal.
'gtty' sets *ATTRIBUTES to describe the terminal attributes of the
terminal which is open with file descriptor FILEDES.
-- Function: int stty (int FILEDES, const struct sgttyb *ATTRIBUTES)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
This function sets the attributes of a terminal.
'stty' sets the terminal attributes of the terminal which is open
with file descriptor FILEDES to those described by *FILEDES.

File: libc.info, Node: Line Control, Next: Noncanon Example, Prev: BSD Terminal Modes, Up: Low-Level Terminal Interface
17.6 Line Control Functions
===========================
These functions perform miscellaneous control actions on terminal
devices. As regards terminal access, they are treated like doing
output: if any of these functions is used by a background process on its
controlling terminal, normally all processes in the process group are
sent a 'SIGTTOU' signal. The exception is if the calling process itself
is ignoring or blocking 'SIGTTOU' signals, in which case the operation
is performed and no signal is sent. *Note Job Control::.
-- Function: int tcsendbreak (int FILEDES, int DURATION)
Preliminary: | MT-Unsafe race:tcattr(filedes)/bsd | AS-Unsafe |
AC-Unsafe corrupt/bsd | *Note POSIX Safety Concepts::.
This function generates a break condition by transmitting a stream
of zero bits on the terminal associated with the file descriptor
FILEDES. The duration of the break is controlled by the DURATION
argument. If zero, the duration is between 0.25 and 0.5 seconds.
The meaning of a nonzero value depends on the operating system.
This function does nothing if the terminal is not an asynchronous
serial data port.
The return value is normally zero. In the event of an error, a
value of -1 is returned. The following 'errno' error conditions
are defined for this function:
'EBADF'
The FILEDES is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal device.
-- Function: int tcdrain (int FILEDES)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
The 'tcdrain' function waits until all queued output to the
terminal FILEDES has been transmitted.
This function is a cancellation point in multi-threaded programs.
This is a problem if the thread allocates some resources (like
memory, file descriptors, semaphores or whatever) at the time
'tcdrain' is called. If the thread gets canceled these resources
stay allocated until the program ends. To avoid this calls to
'tcdrain' should be protected using cancellation handlers.
The return value is normally zero. In the event of an error, a
value of -1 is returned. The following 'errno' error conditions
are defined for this function:
'EBADF'
The FILEDES is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal device.
'EINTR'
The operation was interrupted by delivery of a signal. *Note
Interrupted Primitives::.
-- Function: int tcflush (int FILEDES, int QUEUE)
Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
Concepts::.
The 'tcflush' function is used to clear the input and/or output
queues associated with the terminal file FILEDES. The QUEUE
argument specifies which queue(s) to clear, and can be one of the
following values:
'TCIFLUSH'
Clear any input data received, but not yet read.
'TCOFLUSH'
Clear any output data written, but not yet transmitted.
'TCIOFLUSH'
Clear both queued input and output.
The return value is normally zero. In the event of an error, a
value of -1 is returned. The following 'errno' error conditions
are defined for this function:
'EBADF'
The FILEDES is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal device.
'EINVAL'
A bad value was supplied as the QUEUE argument.
It is unfortunate that this function is named 'tcflush', because
the term "flush" is normally used for quite another
operation--waiting until all output is transmitted--and using it
for discarding input or output would be confusing. Unfortunately,
the name 'tcflush' comes from POSIX and we cannot change it.
-- Function: int tcflow (int FILEDES, int ACTION)
Preliminary: | MT-Unsafe race:tcattr(filedes)/bsd | AS-Unsafe |
AC-Safe | *Note POSIX Safety Concepts::.
The 'tcflow' function is used to perform operations relating to
XON/XOFF flow control on the terminal file specified by FILEDES.
The ACTION argument specifies what operation to perform, and can be
one of the following values:
'TCOOFF'
Suspend transmission of output.
'TCOON'
Restart transmission of output.
'TCIOFF'
Transmit a STOP character.
'TCION'
Transmit a START character.
For more information about the STOP and START characters, see *note
Special Characters::.
The return value is normally zero. In the event of an error, a
value of -1 is returned. The following 'errno' error conditions
are defined for this function:
'EBADF'
The FILEDES is not a valid file descriptor.
'ENOTTY'
The FILEDES is not associated with a terminal device.
'EINVAL'
A bad value was supplied as the ACTION argument.

File: libc.info, Node: Noncanon Example, Next: Pseudo-Terminals, Prev: Line Control, Up: Low-Level Terminal Interface
17.7 Noncanonical Mode Example
==============================
Here is an example program that shows how you can set up a terminal
device to read single characters in noncanonical input mode, without
echo.
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
/* Use this variable to remember original terminal attributes. */
struct termios saved_attributes;
void
reset_input_mode (void)
{
tcsetattr (STDIN_FILENO, TCSANOW, &saved_attributes);
}
void
set_input_mode (void)
{
struct termios tattr;
char *name;
/* Make sure stdin is a terminal. */
if (!isatty (STDIN_FILENO))
{
fprintf (stderr, "Not a terminal.\n");
exit (EXIT_FAILURE);
}
/* Save the terminal attributes so we can restore them later. */
tcgetattr (STDIN_FILENO, &saved_attributes);
atexit (reset_input_mode);
/* Set the funny terminal modes. */
tcgetattr (STDIN_FILENO, &tattr);
tattr.c_lflag &= ~(ICANON|ECHO); /* Clear ICANON and ECHO. */
tattr.c_cc[VMIN] = 1;
tattr.c_cc[VTIME] = 0;
tcsetattr (STDIN_FILENO, TCSAFLUSH, &tattr);
}
int
main (void)
{
char c;
set_input_mode ();
while (1)
{
read (STDIN_FILENO, &c, 1);
if (c == '\004') /* 'C-d' */
break;
else
putchar (c);
}
return EXIT_SUCCESS;
}
This program is careful to restore the original terminal modes before
exiting or terminating with a signal. It uses the 'atexit' function
(*note Cleanups on Exit::) to make sure this is done by 'exit'.
The shell is supposed to take care of resetting the terminal modes
when a process is stopped or continued; see *note Job Control::. But
some existing shells do not actually do this, so you may wish to
establish handlers for job control signals that reset terminal modes.
The above example does so.

File: libc.info, Node: Pseudo-Terminals, Prev: Noncanon Example, Up: Low-Level Terminal Interface
17.8 Pseudo-Terminals
=====================
A "pseudo-terminal" is a special interprocess communication channel that
acts like a terminal. One end of the channel is called the "master"
side or "master pseudo-terminal device", the other side is called the
"slave" side. Data written to the master side is received by the slave
side as if it was the result of a user typing at an ordinary terminal,
and data written to the slave side is sent to the master side as if it
was written on an ordinary terminal.
Pseudo terminals are the way programs like 'xterm' and 'emacs'
implement their terminal emulation functionality.
* Menu:
* Allocation:: Allocating a pseudo terminal.
* Pseudo-Terminal Pairs:: How to open both sides of a
pseudo-terminal in a single operation.

File: libc.info, Node: Allocation, Next: Pseudo-Terminal Pairs, Up: Pseudo-Terminals
17.8.1 Allocating Pseudo-Terminals
----------------------------------
This subsection describes functions for allocating a pseudo-terminal,
and for making this pseudo-terminal available for actual use. These
functions are declared in the header file 'stdlib.h'.
-- Function: int getpt (void)
Preliminary: | MT-Safe | AS-Safe | AC-Safe fd | *Note POSIX Safety
Concepts::.
The 'getpt' function returns a new file descriptor for the next
available master pseudo-terminal. The normal return value from
'getpt' is a non-negative integer file descriptor. In the case of
an error, a value of -1 is returned instead. The following 'errno'
conditions are defined for this function:
'ENOENT'
There are no free master pseudo-terminals available.
This function is a GNU extension.
-- Function: int grantpt (int FILEDES)
Preliminary: | MT-Safe locale | AS-Unsafe dlopen plugin heap lock |
AC-Unsafe corrupt lock fd mem | *Note POSIX Safety Concepts::.
The 'grantpt' function changes the ownership and access permission
of the slave pseudo-terminal device corresponding to the master
pseudo-terminal device associated with the file descriptor FILEDES.
The owner is set from the real user ID of the calling process
(*note Process Persona::), and the group is set to a special group
(typically "tty") or from the real group ID of the calling process.
The access permission is set such that the file is both readable
and writable by the owner and only writable by the group.
On some systems this function is implemented by invoking a special
'setuid' root program (*note How Change Persona::). As a
consequence, installing a signal handler for the 'SIGCHLD' signal
(*note Job Control Signals::) may interfere with a call to
'grantpt'.
The normal return value from 'grantpt' is 0; a value of -1 is
returned in case of failure. The following 'errno' error
conditions are defined for this function:
'EBADF'
The FILEDES argument is not a valid file descriptor.
'EINVAL'
The FILEDES argument is not associated with a master
pseudo-terminal device.
'EACCES'
The slave pseudo-terminal device corresponding to the master
associated with FILEDES could not be accessed.
-- Function: int unlockpt (int FILEDES)
Preliminary: | MT-Safe | AS-Unsafe heap/bsd | AC-Unsafe mem fd |
*Note POSIX Safety Concepts::.
The 'unlockpt' function unlocks the slave pseudo-terminal device
corresponding to the master pseudo-terminal device associated with
the file descriptor FILEDES. On many systems, the slave can only
be opened after unlocking, so portable applications should always
call 'unlockpt' before trying to open the slave.
The normal return value from 'unlockpt' is 0; a value of -1 is
returned in case of failure. The following 'errno' error
conditions are defined for this function:
'EBADF'
The FILEDES argument is not a valid file descriptor.
'EINVAL'
The FILEDES argument is not associated with a master
pseudo-terminal device.
-- Function: char * ptsname (int FILEDES)
Preliminary: | MT-Unsafe race:ptsname | AS-Unsafe heap/bsd |
AC-Unsafe mem fd | *Note POSIX Safety Concepts::.
If the file descriptor FILEDES is associated with a master
pseudo-terminal device, the 'ptsname' function returns a pointer to
a statically-allocated, null-terminated string containing the file
name of the associated slave pseudo-terminal file. This string
might be overwritten by subsequent calls to 'ptsname'.
-- Function: int ptsname_r (int FILEDES, char *BUF, size_t LEN)
Preliminary: | MT-Safe | AS-Unsafe heap/bsd | AC-Unsafe mem fd |
*Note POSIX Safety Concepts::.
The 'ptsname_r' function is similar to the 'ptsname' function
except that it places its result into the user-specified buffer
starting at BUF with length LEN.
This function is a GNU extension.
*Portability Note:* On System V derived systems, the file returned by
the 'ptsname' and 'ptsname_r' functions may be STREAMS-based, and
therefore require additional processing after opening before it actually
behaves as a pseudo terminal.
Typical usage of these functions is illustrated by the following
example:
int
open_pty_pair (int *amaster, int *aslave)
{
int master, slave;
char *name;
master = getpt ();
if (master < 0)
return 0;
if (grantpt (master) < 0 || unlockpt (master) < 0)
goto close_master;
name = ptsname (master);
if (name == NULL)
goto close_master;
slave = open (name, O_RDWR);
if (slave == -1)
goto close_master;
if (isastream (slave))
{
if (ioctl (slave, I_PUSH, "ptem") < 0
|| ioctl (slave, I_PUSH, "ldterm") < 0)
goto close_slave;
}
*amaster = master;
*aslave = slave;
return 1;
close_slave:
close (slave);
close_master:
close (master);
return 0;
}

File: libc.info, Node: Pseudo-Terminal Pairs, Prev: Allocation, Up: Pseudo-Terminals
17.8.2 Opening a Pseudo-Terminal Pair
-------------------------------------
These functions, derived from BSD, are available in the separate
'libutil' library, and declared in 'pty.h'.
-- Function: int openpty (int *AMASTER, int *ASLAVE, char *NAME, const
struct termios *TERMP, const struct winsize *WINP)
Preliminary: | MT-Safe locale | AS-Unsafe dlopen plugin heap lock |
AC-Unsafe corrupt lock fd mem | *Note POSIX Safety Concepts::.
This function allocates and opens a pseudo-terminal pair, returning
the file descriptor for the master in *AMASTER, and the file
descriptor for the slave in *ASLAVE. If the argument NAME is not a
null pointer, the file name of the slave pseudo-terminal device is
stored in '*name'. If TERMP is not a null pointer, the terminal
attributes of the slave are set to the ones specified in the
structure that TERMP points to (*note Terminal Modes::). Likewise,
if the WINP is not a null pointer, the screen size of the slave is
set to the values specified in the structure that WINP points to.
The normal return value from 'openpty' is 0; a value of -1 is
returned in case of failure. The following 'errno' conditions are
defined for this function:
'ENOENT'
There are no free pseudo-terminal pairs available.
*Warning:* Using the 'openpty' function with NAME not set to 'NULL'
is *very dangerous* because it provides no protection against
overflowing the string NAME. You should use the 'ttyname' function
on the file descriptor returned in *SLAVE to find out the file name
of the slave pseudo-terminal device instead.
-- Function: int forkpty (int *AMASTER, char *NAME, const struct
termios *TERMP, const struct winsize *WINP)
Preliminary: | MT-Safe locale | AS-Unsafe dlopen plugin heap lock |
AC-Unsafe corrupt lock fd mem | *Note POSIX Safety Concepts::.
This function is similar to the 'openpty' function, but in
addition, forks a new process (*note Creating a Process::) and
makes the newly opened slave pseudo-terminal device the controlling
terminal (*note Controlling Terminal::) for the child process.
If the operation is successful, there are then both parent and
child processes and both see 'forkpty' return, but with different
values: it returns a value of 0 in the child process and returns
the child's process ID in the parent process.
If the allocation of a pseudo-terminal pair or the process creation
failed, 'forkpty' returns a value of -1 in the parent process.
*Warning:* The 'forkpty' function has the same problems with
respect to the NAME argument as 'openpty'.

File: libc.info, Node: Syslog, Next: Mathematics, Prev: Low-Level Terminal Interface, Up: Top
18 Syslog
*********
This chapter describes facilities for issuing and logging messages of
system administration interest. This chapter has nothing to do with
programs issuing messages to their own users or keeping private logs
(One would typically do that with the facilities described in *note I/O
on Streams::).
Most systems have a facility called "Syslog" that allows programs to
submit messages of interest to system administrators and can be
configured to pass these messages on in various ways, such as printing
on the console, mailing to a particular person, or recording in a log
file for future reference.
A program uses the facilities in this chapter to submit such
messages.
* Menu:
* Overview of Syslog:: Overview of a system's Syslog facility
* Submitting Syslog Messages:: Functions to submit messages to Syslog

File: libc.info, Node: Overview of Syslog, Next: Submitting Syslog Messages, Up: Syslog
18.1 Overview of Syslog
=======================
System administrators have to deal with lots of different kinds of
messages from a plethora of subsystems within each system, and usually
lots of systems as well. For example, an FTP server might report every
connection it gets. The kernel might report hardware failures on a disk
drive. A DNS server might report usage statistics at regular intervals.
Some of these messages need to be brought to a system administrator's
attention immediately. And it may not be just any system administrator
- there may be a particular system administrator who deals with a
particular kind of message. Other messages just need to be recorded for
future reference if there is a problem. Still others may need to have
information extracted from them by an automated process that generates
monthly reports.
To deal with these messages, most Unix systems have a facility called
"Syslog." It is generally based on a daemon called "Syslogd" Syslogd
listens for messages on a Unix domain socket named '/dev/log'. Based on
classification information in the messages and its configuration file
(usually '/etc/syslog.conf'), Syslogd routes them in various ways. Some
of the popular routings are:
* Write to the system console
* Mail to a specific user
* Write to a log file
* Pass to another daemon
* Discard
Syslogd can also handle messages from other systems. It listens on
the 'syslog' UDP port as well as the local socket for messages.
Syslog can handle messages from the kernel itself. But the kernel
doesn't write to '/dev/log'; rather, another daemon (sometimes called
"Klogd") extracts messages from the kernel and passes them on to Syslog
as any other process would (and it properly identifies them as messages
from the kernel).
Syslog can even handle messages that the kernel issued before Syslogd
or Klogd was running. A Linux kernel, for example, stores startup
messages in a kernel message ring and they are normally still there when
Klogd later starts up. Assuming Syslogd is running by the time Klogd
starts, Klogd then passes everything in the message ring to it.
In order to classify messages for disposition, Syslog requires any
process that submits a message to it to provide two pieces of
classification information with it:
facility
This identifies who submitted the message. There are a small
number of facilities defined. The kernel, the mail subsystem, and
an FTP server are examples of recognized facilities. For the
complete list, *Note syslog; vsyslog::. Keep in mind that these
are essentially arbitrary classifications. "Mail subsystem"
doesn't have any more meaning than the system administrator gives
to it.
priority
This tells how important the content of the message is. Examples
of defined priority values are: debug, informational, warning,
critical. For the complete list, see *note syslog; vsyslog::.
Except for the fact that the priorities have a defined order, the
meaning of each of these priorities is entirely determined by the
system administrator.
A "facility/priority" is a number that indicates both the facility
and the priority.
*Warning:* This terminology is not universal. Some people use
"level" to refer to the priority and "priority" to refer to the
combination of facility and priority. A Linux kernel has a concept of a
message "level," which corresponds both to a Syslog priority and to a
Syslog facility/priority (It can be both because the facility code for
the kernel is zero, and that makes priority and facility/priority the
same value).
The GNU C Library provides functions to submit messages to Syslog.
They do it by writing to the '/dev/log' socket. *Note Submitting Syslog
Messages::.
The GNU C Library functions only work to submit messages to the
Syslog facility on the same system. To submit a message to the Syslog
facility on another system, use the socket I/O functions to write a UDP
datagram to the 'syslog' UDP port on that system. *Note Sockets::.

File: libc.info, Node: Submitting Syslog Messages, Prev: Overview of Syslog, Up: Syslog
18.2 Submitting Syslog Messages
===============================
The GNU C Library provides functions to submit messages to the Syslog
facility:
* Menu:
* openlog:: Open connection to Syslog
* syslog; vsyslog:: Submit message to Syslog
* closelog:: Close connection to Syslog
* setlogmask:: Cause certain messages to be ignored
* Syslog Example:: Example of all of the above
These functions only work to submit messages to the Syslog facility
on the same system. To submit a message to the Syslog facility on
another system, use the socket I/O functions to write a UDP datagram to
the 'syslog' UDP port on that system. *Note Sockets::.

File: libc.info, Node: openlog, Next: syslog; vsyslog, Up: Submitting Syslog Messages
18.2.1 openlog
--------------
The symbols referred to in this section are declared in the file
'syslog.h'.
-- Function: void openlog (const char *IDENT, int OPTION, int FACILITY)
Preliminary: | MT-Safe | AS-Unsafe lock | AC-Unsafe lock fd | *Note
POSIX Safety Concepts::.
'openlog' opens or reopens a connection to Syslog in preparation
for submitting messages.
IDENT is an arbitrary identification string which future 'syslog'
invocations will prefix to each message. This is intended to
identify the source of the message, and people conventionally set
it to the name of the program that will submit the messages.
If IDENT is NULL, or if 'openlog' is not called, the default
identification string used in Syslog messages will be the program
name, taken from argv[0].
Please note that the string pointer IDENT will be retained
internally by the Syslog routines. You must not free the memory
that IDENT points to. It is also dangerous to pass a reference to
an automatic variable since leaving the scope would mean ending the
lifetime of the variable. If you want to change the IDENT string,
you must call 'openlog' again; overwriting the string pointed to by
IDENT is not thread-safe.
You can cause the Syslog routines to drop the reference to IDENT
and go back to the default string (the program name taken from
argv[0]), by calling 'closelog': *Note closelog::.
In particular, if you are writing code for a shared library that
might get loaded and then unloaded (e.g. a PAM module), and you
use 'openlog', you must call 'closelog' before any point where your
library might get unloaded, as in this example:
#include <syslog.h>
void
shared_library_function (void)
{
openlog ("mylibrary", option, priority);
syslog (LOG_INFO, "shared library has been invoked");
closelog ();
}
Without the call to 'closelog', future invocations of 'syslog' by
the program using the shared library may crash, if the library gets
unloaded and the memory containing the string '"mylibrary"' becomes
unmapped. This is a limitation of the BSD syslog interface.
'openlog' may or may not open the '/dev/log' socket, depending on
OPTION. If it does, it tries to open it and connect it as a stream
socket. If that doesn't work, it tries to open it and connect it
as a datagram socket. The socket has the "Close on Exec"
attribute, so the kernel will close it if the process performs an
exec.