man/man3/Tcl_Exit.3 - toolchains/skids - Git at Google

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 See the \\fBoptions\\fR manual entry for details on the standard options.
 ..
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 .TH Tcl_Exit 3 8.1 Tcl "Tcl Library Procedures"
 .BS
 .SH NAME
 Tcl_Exit, Tcl_Finalize, Tcl_CreateExitHandler, Tcl_DeleteExitHandler, Tcl_ExitThread, Tcl_FinalizeThread, Tcl_CreateThreadExitHandler, Tcl_DeleteThreadExitHandler \- end the application or thread (and invoke exit handlers)
 .SH SYNOPSIS
 .nf
 \fB#include <tcl.h>\fR
 .sp
 \fBTcl_Exit\fR(\fIstatus\fR)
 .sp
 \fBTcl_Finalize\fR()
 .sp
 \fBTcl_CreateExitHandler\fR(\fIproc, clientData\fR)
 .sp
 \fBTcl_DeleteExitHandler\fR(\fIproc, clientData\fR)
 .sp
 \fBTcl_ExitThread\fR(\fIstatus\fR)
 .sp
 \fBTcl_FinalizeThread\fR()
 .sp
 \fBTcl_CreateThreadExitHandler\fR(\fIproc, clientData\fR)
 .sp
 \fBTcl_DeleteThreadExitHandler\fR(\fIproc, clientData\fR)
 .SH ARGUMENTS
 .AS Tcl_ExitProc clientData
 .AP int status  in
 Provides information about why the application or thread exited.
 Exact meaning may
 be platform-specific.  0 usually means a normal exit, any nonzero value
 usually means that an error occurred.
 .AP Tcl_ExitProc *proc in
 Procedure to invoke before exiting application.
 .AP ClientData clientData in
 Arbitrary one-word value to pass to \fIproc\fR.
 .BE

 .SH DESCRIPTION
 .PP
 The procedures described here provide a graceful mechanism to end the
 execution of a \fBTcl\fR application. Exit handlers are invoked to cleanup the
 application's state before ending the execution of \fBTcl\fR code.
 .PP
 Invoke \fBTcl_Exit\fR to end a \fBTcl\fR application and to exit from this
 process. This procedure is invoked by the \fBexit\fR command, and can be
 invoked anyplace else to terminate the application.
 No-one should ever invoke the \fBexit\fR system procedure directly;  always
 invoke \fBTcl_Exit\fR instead, so that it can invoke exit handlers.
 Note that if other code invokes \fBexit\fR system procedure directly, or
 otherwise causes the application to terminate without calling
 \fBTcl_Exit\fR, the exit handlers will not be run.
 \fBTcl_Exit\fR internally invokes the \fBexit\fR system call, thus it never
 returns control to its caller.
 .PP
 \fBTcl_Finalize\fR is similar to \fBTcl_Exit\fR except that it does not
 exit from the current process.
 It is useful for cleaning up when a process is finished using \fBTcl\fR but
 wishes to continue executing, and when \fBTcl\fR is used in a dynamically
 loaded extension that is about to be unloaded.
 On some systems \fBTcl\fR is automatically notified when it is being
 unloaded, and it calls \fBTcl_Finalize\fR internally; on these systems it
 not necessary for the caller to explicitly call \fBTcl_Finalize\fR.
 However, to ensure portability, your code should always invoke
 \fBTcl_Finalize\fR when \fBTcl\fR is being unloaded, to ensure that the
 code will work on all platforms. \fBTcl_Finalize\fR can be safely called
 more than once.
 .PP
 .VS
 \fBTcl_ExitThread\fR is used to terminate the current thread and invoke
 per-thread exit handlers.  This finalization is done by
 \fBTcl_FinalizeThread\fR, which you can call if you just want to clean
 up per-thread state and invoke the thread exit handlers.
 \fBTcl_Finalize\fR calls \fBTcl_FinalizeThread\fR for the current
 thread automatically.
 .VE
 .PP
 \fBTcl_CreateExitHandler\fR arranges for \fIproc\fR to be invoked
 by \fBTcl_Finalize\fR and \fBTcl_Exit\fR.
 \fBTcl_CreateThreadExitHandler\fR arranges for \fIproc\fR to be invoked
 by \fBTcl_FinalizeThread\fR and \fBTcl_ExitThread\fR.
 This provides a hook for cleanup operations such as flushing buffers
 and freeing global memory.
 \fIProc\fR should match the type \fBTcl_ExitProc\fR:
 .CS
 typedef void Tcl_ExitProc(ClientData \fIclientData\fR);
 .CE
 The \fIclientData\fR parameter to \fIproc\fR is a
 copy of the \fIclientData\fR argument given to
 \fBTcl_CreateExitHandler\fR or \fBTcl_CreateThreadExitHandler\fR when
 the callback
 was created.  Typically, \fIclientData\fR points to a data
 structure containing application-specific information about
 what to do in \fIproc\fR.
 .PP
 \fBTcl_DeleteExitHandler\fR and \fBTcl_DeleteThreadExitHandler\fR may be
 called to delete a
 previously-created exit handler.  It removes the handler
 indicated by \fIproc\fR and \fIclientData\fR so that no call
 to \fIproc\fR will be made.  If no such handler exists then
 \fBTcl_DeleteExitHandler\fR or \fBTcl_DeleteThreadExitHandler\fR does nothing.
 .PP
 .VS
 .PP
 \fBTcl_Finalize\fR and \fBTcl_Exit\fR execute all registered exit handlers,
 in reverse order from the order in which they were registered.
 This matches the natural order in which extensions are loaded and unloaded;
 if extension \fBA\fR loads extension \fBB\fR, it usually
 unloads \fBB\fR before it itself is unloaded.
 If extension \fBA\fR registers its exit handlers before loading extension
 \fBB\fR, this ensures that any exit handlers for \fBB\fR will be executed
 before the exit handlers for \fBA\fR.
 .VE
 .VS
 .PP
 \fBTcl_Finalize\fR and \fBTcl_Exit\fR call \fBTcl_FinalizeThread\fR
 and the thread exit handlers \fIafter\fR
 the process-wide exit handlers.  This is because thread finalization shuts
 down the I/O channel system, so any attempt at I/O by the global exit
 handlers will vanish into the bitbucket.
 .VE

 .SH KEYWORDS
 callback, cleanup, dynamic loading, end application, exit, unloading, thread
	'\"
	'\" Copyright (c) 1995-1996 Sun Microsystems, Inc.
	'\"
	'\" See the file "license.terms" for information on usage and redistribution
	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	'\"
	'\" RCS: @(#) $Id: Exit.3,v 1.4 2000/07/24 00:03:02 jenglish Exp $
	'\"
	'\" The definitions below are for supplemental macros used in Tcl/Tk
	'\" manual entries.
	'\"
	'\" .AP type name in/out ?indent?
	'\" Start paragraph describing an argument to a library procedure.
	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	'\" or "in/out" to describe whether procedure reads or modifies arg,
	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	'\" needed; use .AS below instead)
	'\"
	'\" .AS ?type? ?name?
	'\" Give maximum sizes of arguments for setting tab stops. Type and
	'\" name are examples of largest possible arguments that will be passed
	'\" to .AP later. If args are omitted, default tab stops are used.
	'\"
	'\" .BS
	'\" Start box enclosure. From here until next .BE, everything will be
	'\" enclosed in one large box.
	'\"
	'\" .BE
	'\" End of box enclosure.
	'\"
	'\" .CS
	'\" Begin code excerpt.
	'\"
	'\" .CE
	'\" End code excerpt.
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	'\" .VS ?version? ?br?
	'\" Begin vertical sidebar, for use in marking newly-changed parts
	'\" of man pages. The first argument is ignored and used for recording
	'\" the version when the .VS was added, so that the sidebars can be
	'\" found and removed when they reach a certain age. If another argument
	'\" is present, then a line break is forced before starting the sidebar.
	'\"
	'\" .VE
	'\" End of vertical sidebar.
	'\"
	'\" .DS
	'\" Begin an indented unfilled display.
	'\"
	'\" .DE
	'\" End of indented unfilled display.
	'\"
	'\" .SO
	'\" Start of list of standard options for a Tk widget. The
	'\" options follow on successive lines, in four columns separated
	'\" by tabs.
	'\"
	'\" .SE
	'\" End of list of standard options for a Tk widget.
	'\"
	'\" .OP cmdName dbName dbClass
	'\" Start of description of a specific option. cmdName gives the
	'\" option's name as specified in the class command, dbName gives
	'\" the option's name in the option database, and dbClass gives
	'\" the option's class in the option database.
	'\"
	'\" .UL arg1 arg2
	'\" Print arg1 underlined, then print arg2 normally.
	'\"
	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
	'\"
	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
	.if t .wh -1.3i ^B
	.nr ^l \n(.l
	.ad b
	'\" # Start an argument description
	.de AP
	.ie !"\\$4"" .TP \\$4
	.el \{\
	. ie !"\\$2"" .TP \\n()Cu
	. el .TP 15
	.\}
	.ta \\n()Au \\n()Bu
	.ie !"\\$3"" \{\
	\&\\$1 \\fI\\$2\\fP (\\$3)
	.\".b
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	.nr )A 10n
	.if !"\\$1"" .nr )A \\w'\\$1'u+3n
	.nr )B \\n()Au+15n
	.\"
	.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
	.nr )C \\n()Bu+\\w'(in/out)'u+2n
	..
	.AS Tcl_Interp Tcl_CreateInterp in/out
	'\" # BS - start boxed text
	'\" # ^y = starting y location
	'\" # ^b = 1
	.de BS
	.br
	.mk ^y
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	.\" box if the box started on an earlier page.
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	\h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
	.\}
	.el \}\
	\h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
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	.\" draw two sides but no top otherwise.
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	.\}
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	.LP
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	.ta 5.5c 11c
	.ft B
	..
	'\" # SE - end of list of standard options
	.de SE
	.fi
	.ft R
	.LP
	See the \\fBoptions\\fR manual entry for details on the standard options.
	..
	'\" # OP - start of full description for a single option
	.de OP
	.LP
	.nf
	.ta 4c
	Command-Line Name: \\fB\\$1\\fR
	Database Name: \\fB\\$2\\fR
	Database Class: \\fB\\$3\\fR
	.fi
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	..
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	.fi
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	..
	.de UL
	\\$1\l'\|0\(ul'\\$2
	..
	.TH Tcl_Exit 3 8.1 Tcl "Tcl Library Procedures"
	.BS
	.SH NAME
	Tcl_Exit, Tcl_Finalize, Tcl_CreateExitHandler, Tcl_DeleteExitHandler, Tcl_ExitThread, Tcl_FinalizeThread, Tcl_CreateThreadExitHandler, Tcl_DeleteThreadExitHandler \- end the application or thread (and invoke exit handlers)
	.SH SYNOPSIS
	.nf
	\fB#include <tcl.h>\fR
	.sp
	\fBTcl_Exit\fR(\fIstatus\fR)
	.sp
	\fBTcl_Finalize\fR()
	.sp
	\fBTcl_CreateExitHandler\fR(\fIproc, clientData\fR)
	.sp
	\fBTcl_DeleteExitHandler\fR(\fIproc, clientData\fR)
	.sp
	\fBTcl_ExitThread\fR(\fIstatus\fR)
	.sp
	\fBTcl_FinalizeThread\fR()
	.sp
	\fBTcl_CreateThreadExitHandler\fR(\fIproc, clientData\fR)
	.sp
	\fBTcl_DeleteThreadExitHandler\fR(\fIproc, clientData\fR)
	.SH ARGUMENTS
	.AS Tcl_ExitProc clientData
	.AP int status in
	Provides information about why the application or thread exited.
	Exact meaning may
	be platform-specific. 0 usually means a normal exit, any nonzero value
	usually means that an error occurred.
	.AP Tcl_ExitProc *proc in
	Procedure to invoke before exiting application.
	.AP ClientData clientData in
	Arbitrary one-word value to pass to \fIproc\fR.
	.BE

	.SH DESCRIPTION
	.PP
	The procedures described here provide a graceful mechanism to end the
	execution of a \fBTcl\fR application. Exit handlers are invoked to cleanup the
	application's state before ending the execution of \fBTcl\fR code.
	.PP
	Invoke \fBTcl_Exit\fR to end a \fBTcl\fR application and to exit from this
	process. This procedure is invoked by the \fBexit\fR command, and can be
	invoked anyplace else to terminate the application.
	No-one should ever invoke the \fBexit\fR system procedure directly; always
	invoke \fBTcl_Exit\fR instead, so that it can invoke exit handlers.
	Note that if other code invokes \fBexit\fR system procedure directly, or
	otherwise causes the application to terminate without calling
	\fBTcl_Exit\fR, the exit handlers will not be run.
	\fBTcl_Exit\fR internally invokes the \fBexit\fR system call, thus it never
	returns control to its caller.
	.PP
	\fBTcl_Finalize\fR is similar to \fBTcl_Exit\fR except that it does not
	exit from the current process.
	It is useful for cleaning up when a process is finished using \fBTcl\fR but
	wishes to continue executing, and when \fBTcl\fR is used in a dynamically
	loaded extension that is about to be unloaded.
	On some systems \fBTcl\fR is automatically notified when it is being
	unloaded, and it calls \fBTcl_Finalize\fR internally; on these systems it
	not necessary for the caller to explicitly call \fBTcl_Finalize\fR.
	However, to ensure portability, your code should always invoke
	\fBTcl_Finalize\fR when \fBTcl\fR is being unloaded, to ensure that the
	code will work on all platforms. \fBTcl_Finalize\fR can be safely called
	more than once.
	.PP
	.VS
	\fBTcl_ExitThread\fR is used to terminate the current thread and invoke
	per-thread exit handlers. This finalization is done by
	\fBTcl_FinalizeThread\fR, which you can call if you just want to clean
	up per-thread state and invoke the thread exit handlers.
	\fBTcl_Finalize\fR calls \fBTcl_FinalizeThread\fR for the current
	thread automatically.
	.VE
	.PP
	\fBTcl_CreateExitHandler\fR arranges for \fIproc\fR to be invoked
	by \fBTcl_Finalize\fR and \fBTcl_Exit\fR.
	\fBTcl_CreateThreadExitHandler\fR arranges for \fIproc\fR to be invoked
	by \fBTcl_FinalizeThread\fR and \fBTcl_ExitThread\fR.
	This provides a hook for cleanup operations such as flushing buffers
	and freeing global memory.
	\fIProc\fR should match the type \fBTcl_ExitProc\fR:
	.CS
	typedef void Tcl_ExitProc(ClientData \fIclientData\fR);
	.CE
	The \fIclientData\fR parameter to \fIproc\fR is a
	copy of the \fIclientData\fR argument given to
	\fBTcl_CreateExitHandler\fR or \fBTcl_CreateThreadExitHandler\fR when
	the callback
	was created. Typically, \fIclientData\fR points to a data
	structure containing application-specific information about
	what to do in \fIproc\fR.
	.PP
	\fBTcl_DeleteExitHandler\fR and \fBTcl_DeleteThreadExitHandler\fR may be
	called to delete a
	previously-created exit handler. It removes the handler
	indicated by \fIproc\fR and \fIclientData\fR so that no call
	to \fIproc\fR will be made. If no such handler exists then
	\fBTcl_DeleteExitHandler\fR or \fBTcl_DeleteThreadExitHandler\fR does nothing.
	.PP
	.VS
	.PP
	\fBTcl_Finalize\fR and \fBTcl_Exit\fR execute all registered exit handlers,
	in reverse order from the order in which they were registered.
	This matches the natural order in which extensions are loaded and unloaded;
	if extension \fBA\fR loads extension \fBB\fR, it usually
	unloads \fBB\fR before it itself is unloaded.
	If extension \fBA\fR registers its exit handlers before loading extension
	\fBB\fR, this ensures that any exit handlers for \fBB\fR will be executed
	before the exit handlers for \fBA\fR.
	.VE
	.VS
	.PP
	\fBTcl_Finalize\fR and \fBTcl_Exit\fR call \fBTcl_FinalizeThread\fR
	and the thread exit handlers \fIafter\fR
	the process-wide exit handlers. This is because thread finalization shuts
	down the I/O channel system, so any attempt at I/O by the global exit
	handlers will vanish into the bitbucket.
	.VE

	.SH KEYWORDS
	callback, cleanup, dynamic loading, end application, exit, unloading, thread