'\"
'\" Copyright (c) 1994 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tk_Main 3tk 4.0 Tk "Tk Library Procedures"
.\" The -*- nroff -*- 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
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.\"	name are examples of largest possible arguments that will be passed
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.\"	found and removed when they reach a certain age.  If another argument
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.\" .SO ?manpage?
.\"	Start of list of standard options for a Tk widget. The manpage
.\"	argument defines where to look up the standard options; if
.\"	omitted, defaults to "options". The options follow on successive
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.\"
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.\"	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
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.\" .UL arg1 arg2
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.\"	(for trailing punctuation) and then a closing parenthesis.
.\"
.\"	# 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
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.el \{\
\&\\fI\\$1\\fP
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..
.\"	# 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
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.\"	# ^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
..
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.\"	# ^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
..
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.de VE
.ie n 'mc
.el \{\
.ev 2
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\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n'
.sp -1
.fi
.ev
.\}
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.\"	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
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.if \\n(^v \{\
.mk ^Y
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..
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.nf
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..
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.RE
.sp
..
.\"	# SO - start of list of standard options
.de SO
'ie '\\$1'' .ds So \\fBoptions\\fR
'el .ds So \\fB\\$1\\fR
.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 \\*(So manual entry for details on the standard options.
..
.\"	# OP - start of full description for a single option
.de OOP
.LP
.nf
.ta 4c
Command-Line Name:	\\fB\\$1\\fR
Database Name:	\\fB\\$2\\fR
Database Class:	\\fB\\$3\\fR
.fi
.IP
..
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.de UL
\\$1\l'|0\(ul'\\$2
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..
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.\"" fix emacs highlighting
.el (\\*(lq\\$1\\*(rq\\$2)\\$3
..
.\"	# QR - quoted range
.de QR
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.\"" fix emacs highlighting
.el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3
..
.\"	# MT - "empty" string
.de MT
.QW ""
..
.BS
.SH NAME
Tk_Main \- main program for Tk-based applications
.SH SYNOPSIS
.nf
\fB#include <tk.h>\fR
.sp
\fBTk_Main\fR(\fIargc, argv, appInitProc\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. On Windows, when
using -DUNICODE, the parameter type changes to wchar_t *.
.AP Tcl_AppInitProc *appInitProc in
Address of an application-specific initialization procedure.
The value for this argument is usually \fBTcl_AppInit\fR.
.BE
.SH DESCRIPTION
.PP
\fBTk_Main\fR acts as the main program for most Tk-based applications.
Starting with Tk 4.0 it is not called \fBmain\fR anymore because it
is part of the Tk library and having a function \fBmain\fR
in a library (particularly a shared library) causes problems on many
systems.
Having \fBmain\fR in the Tk library would also make it hard to use
Tk in C++ programs, since C++ programs must have special C++
\fBmain\fR functions.
.PP
Normally each application contains a small \fBmain\fR function that does
nothing but invoke \fBTk_Main\fR.
\fBTk_Main\fR then does all the work of creating and running a
\fBwish\fR-like application.
.PP
When it is has finished its own initialization, but before
it processes commands, \fBTk_Main\fR calls the procedure given by
the \fIappInitProc\fR argument.  This procedure provides a
.QW hook
for the application to perform its own initialization, such as defining
application-specific commands.  The procedure must have an interface
that matches the type \fBTcl_AppInitProc\fR:
.CS
typedef int \fBTcl_AppInitProc\fR(
        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
\fBTk_Main\fR functions much the same as \fBTcl_Main\fR.  In particular,
\fBTk_Main\fR supports both an interactive mode and a startup script
mode, with the file name and encoding of a startup script under the
control of the \fBTcl_SetStartupScript\fR and \fBTcl_GetStartupScript\fR
routines. However it calls \fBTk_MainLoop\fR after processing any
supplied script, and in interactive uses events registered with
\fBTcl_CreateFileHandler\fR to process user input.
.SH "SEE ALSO"
Tcl_DoOneEvent(3tk)
.SH KEYWORDS
application-specific initialization, command-line arguments, main program