| '\" |
| '\" Copyright (c) 1994 The Regents of the University of California. |
| '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. |
| '\" Copyright (c) 2000 Ajuba Solutions. |
| '\" |
| '\" See the file "license.terms" for information on usage and redistribution |
| '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
| '\" |
| '\" RCS: @(#) $Id: Tcl_Main.3,v 1.9 2002/07/01 18:24:39 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. |
| '\" |
| '\" .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 |
| .\} |
| .el \{\ |
| .br |
| .ie !"\\$2"" \{\ |
| \&\\$1 \\fI\\$2\\fP |
| .\} |
| .el \{\ |
| \&\\fI\\$1\\fP |
| .\} |
| .\} |
| .. |
| '\" # define tabbing values for .AP |
| .de AS |
| .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 |
| .nr ^b 1u |
| .if n .nf |
| .if n .ti 0 |
| .if n \l'\\n(.lu\(ul' |
| .if n .fi |
| .. |
| '\" # BE - end boxed text (draw box now) |
| .de BE |
| .nf |
| .ti 0 |
| .mk ^t |
| .ie n \l'\\n(^lu\(ul' |
| .el \{\ |
| .\" Draw four-sided box normally, but don't draw top of |
| .\" box if the box started on an earlier page. |
| .ie !\\n(^b-1 \{\ |
| \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' |
| .\} |
| .\} |
| .fi |
| .br |
| .nr ^b 0 |
| .. |
| '\" # VS - start vertical sidebar |
| '\" # ^Y = starting y location |
| '\" # ^v = 1 (for troff; for nroff this doesn't matter) |
| .de VS |
| .if !"\\$2"" .br |
| .mk ^Y |
| .ie n 'mc \s12\(br\s0 |
| .el .nr ^v 1u |
| .. |
| '\" # VE - end of vertical sidebar |
| .de VE |
| .ie n 'mc |
| .el \{\ |
| .ev 2 |
| .nf |
| .ti 0 |
| .mk ^t |
| \h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n' |
| .sp -1 |
| .fi |
| .ev |
| .\} |
| .nr ^v 0 |
| .. |
| '\" # Special macro to handle page bottom: finish off current |
| '\" # box/sidebar if in box/sidebar mode, then invoked standard |
| '\" # page bottom macro. |
| .de ^B |
| .ev 2 |
| 'ti 0 |
| 'nf |
| .mk ^t |
| .if \\n(^b \{\ |
| .\" Draw three-sided box if this is the box's first page, |
| .\" draw two sides but no top otherwise. |
| .ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| .el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| .\} |
| .if \\n(^v \{\ |
| .nr ^x \\n(^tu+1v-\\n(^Yu |
| \kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c |
| .\} |
| .bp |
| 'fi |
| .ev |
| .if \\n(^b \{\ |
| .mk ^y |
| .nr ^b 2 |
| .\} |
| .if \\n(^v \{\ |
| .mk ^Y |
| .\} |
| .. |
| '\" # DS - begin display |
| .de DS |
| .RS |
| .nf |
| .sp |
| .. |
| '\" # DE - end display |
| .de DE |
| .fi |
| .RE |
| .sp |
| .. |
| '\" # SO - start of list of standard options |
| .de SO |
| .SH "STANDARD OPTIONS" |
| .LP |
| .nf |
| .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 |
| .IP |
| .. |
| '\" # CS - begin code excerpt |
| .de CS |
| .RS |
| .nf |
| .ta .25i .5i .75i 1i |
| .. |
| '\" # CE - end code excerpt |
| .de CE |
| .fi |
| .RE |
| .. |
| .de UL |
| \\$1\l'|0\(ul'\\$2 |
| .. |
| .TH Tcl_Main 3 8.4 Tcl "Tcl Library Procedures" |
| .BS |
| .SH NAME |
| Tcl_Main, Tcl_SetMainLoop \- main program and event loop definition for Tcl-based applications |
| .SH SYNOPSIS |
| .nf |
| \fB#include <tcl.h>\fR |
| .sp |
| \fBTcl_Main\fR(\fIargc, argv, appInitProc\fR) |
| .sp |
| \fBTcl_SetMainLoop\fR(\fImainLoopProc\fR) |
| .SH ARGUMENTS |
| .AS Tcl_AppInitProc *appInitProc |
| .AP int argc in |
| Number of elements in \fIargv\fR. |
| .AP char *argv[] in |
| Array of strings containing command-line arguments. |
| .AP Tcl_AppInitProc *appInitProc in |
| Address of an application-specific initialization procedure. |
| The value for this argument is usually \fBTcl_AppInit\fR. |
| .AP Tcl_MainLoopProc *mainLoopProc in |
| Address of an application-specific event loop procedure. |
| .BE |
| |
| .SH DESCRIPTION |
| .PP |
| \fBTcl_Main\fR can serve as the main program for Tcl-based shell |
| applications. A ``shell application'' is a program |
| like tclsh or wish that supports both interactive interpretation |
| of Tcl and evaluation of a script contained in a file given as |
| a command line argument. \fBTcl_Main\fR is offered as a convenience |
| to developers of shell applications, so they do not have to |
| reproduce all of the code for proper initialization of the Tcl |
| library and interactive shell operation. Other styles of embedding |
| Tcl in an application are not supported by \fBTcl_Main\fR. Those |
| must be achieved by calling lower level functions in the Tcl library |
| directly. |
| |
| The \fBTcl_Main\fR function has been offered by the Tcl library |
| since release Tcl 7.4. In older releases of Tcl, the Tcl library |
| itself defined a function \fBmain\fR, but that lacks flexibility |
| of embedding style and having a function \fBmain\fR in a library |
| (particularly a shared library) causes problems on many systems. |
| Having \fBmain\fR in the Tcl library would also make it hard to use |
| Tcl in C++ programs, since C++ programs must have special C++ |
| \fBmain\fR functions. |
| .PP |
| Normally each shell application contains a small \fBmain\fR function |
| that does nothing but invoke \fBTcl_Main\fR. |
| \fBTcl_Main\fR then does all the work of creating and running a |
| \fBtclsh\fR-like application. |
| .PP |
| \fBTcl_Main\fR is not provided by the public interface of Tcl's |
| stub library. Programs that call \fBTcl_Main\fR must be linked |
| against the standard Tcl library. Extensions (stub-enabled or |
| not) are not intended to call \fBTcl_Main\fR. |
| .PP |
| \fBTcl_Main\fR is not thread-safe. It should only be called by |
| a single master thread of a multi-threaded application. This |
| restriction is not a problem with normal use described above. |
| .PP |
| \fBTcl_Main\fR and therefore all applications based upon it, like |
| \fBtclsh\fR, use \fBTcl_GetStdChannel\fR to initialize the standard |
| channels to their default values. See \fBTcl_StandardChannels\fR for |
| more information. |
| .PP |
| \fBTcl_Main\fR supports two modes of operation, depending on the |
| values of \fIargc\fR and \fIargv\fR. If \fIargv[1]\fR exists and |
| does not begin with the character \fI-\fR, it is taken to be the |
| name of a file containing a \fIstartup script\fR, which \fBTcl_Main\fR |
| will attempt to evaluate. Otherwise, \fBTcl_Main\fR will enter an |
| interactive mode. |
| .PP |
| In either mode, \fBTcl_Main\fR will define in its master interpreter |
| the Tcl variables \fIargc\fR, \fIargv\fR, \fIargv0\fR, and |
| \fItcl_interactive\fR, as described in the documentation for \fBtclsh\fR. |
| .PP |
| When it has finished its own initialization, but before it processes |
| commands, \fBTcl_Main\fR calls the procedure given by the |
| \fIappInitProc\fR argument. This procedure provides a ``hook'' for |
| the application to perform its own initialization of the interpreter |
| created by \fBTcl_Main\fR, such as defining application-specific |
| commands. The procedure must have an interface that matches the |
| type \fBTcl_AppInitProc\fR: |
| .CS |
| typedef int Tcl_AppInitProc(Tcl_Interp *\fIinterp\fR); |
| .CE |
| |
| \fIAppInitProc\fR is almost always a pointer to \fBTcl_AppInit\fR; for more |
| details on this procedure, see the documentation for \fBTcl_AppInit\fR. |
| .PP |
| When the \fIappInitProc\fR is finished, \fBTcl_Main\fR enters one |
| of its two modes. If a startup script has been provided, \fBTcl_Main\fR |
| attempts to evaluate it. Otherwise, interactive mode begins with |
| examination of the variable \fItcl_rcFileName\fR in the master |
| interpreter. If that variable exists and holds the name of a readable |
| file, the contents of that file are evaluated in the master interpreter. |
| Then interactive operations begin, |
| with prompts and command evaluation results written to the standard |
| output channel, and commands read from the standard input channel |
| and then evaluated. The prompts written to the standard output |
| channel may be customized by defining the Tcl variables \fItcl_prompt1\fR |
| and \fItcl_prompt2\fR as described in the documentation for \fBtclsh\fR. |
| The prompts and command evaluation results are written to the standard |
| output channel only if the Tcl variable \fItcl_interactive\fR in the |
| master interpreter holds a non-zero integer value. |
| .PP |
| .VS 8.4 |
| \fBTcl_SetMainLoop\fR allows setting an event loop procedure to be run. |
| This allows, for example, Tk to be dynamically loaded and set its event |
| loop. The event loop will run following the startup script. If you |
| are in interactive mode, setting the main loop procedure will cause the |
| prompt to become fileevent based and then the loop procedure is called. |
| When the loop procedure returns in interactive mode, interactive operation |
| will continue. |
| The main loop procedure must have an interface that matches the type |
| \fBTcl_MainLoopProc\fR: |
| .CS |
| typedef void Tcl_MainLoopProc(void); |
| .CE |
| .VE 8.4 |
| .PP |
| \fBTcl_Main\fR does not return. Normally a program based on |
| \fBTcl_Main\fR will terminate when the \fBexit\fR command is |
| evaluated. In interactive mode, if an EOF or channel error |
| is encountered on the standard input channel, then \fBTcl_Main\fR |
| itself will evaluate the \fBexit\fR command after the main loop |
| procedure (if any) returns. In non-interactive mode, after |
| \fBTcl_Main\fR evaluates the startup script, and the main loop |
| procedure (if any) returns, \fBTcl_Main\fR will also evaluate |
| the \fBexit\fR command. |
| |
| .SH "SEE ALSO" |
| tclsh(1), Tcl_GetStdChannel(3), Tcl_StandardChannels(3), Tcl_AppInit(3), |
| exit(n) |
| |
| .SH KEYWORDS |
| application-specific initialization, command-line arguments, main program |