getoption.3

linux系统下的音频通信

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'\" Copyright (c) 1990 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
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'\" SCCS: @(#) GetOption.3 1.9 96/03/26 18:11:11
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.so man.macros
.TH Tk_GetOption 3 "" Tk "Tk Library Procedures"
.BS
.SH NAME
Tk_GetOption \- retrieve an option from the option database
.SH SYNOPSIS
.nf
\fB#include <tk.h>\fR
.sp
Tk_Uid
\fBTk_GetOption\fR(\fItkwin, name, class\fR)
.SH ARGUMENTS
.AS Tk_Window *class
.AP Tk_Window tkwin in
Token for window.
.AP char *name in
Name of desired option.
.AP char *class in
Class of desired option.  Null means there is no class for
this option;  do lookup based on name only.
.BE

.SH DESCRIPTION
.PP
This procedure is invoked to retrieve an option from the database
associated with \fItkwin\fR's main window.  If there is an option
for \fItkwin\fR that matches the given \fIname\fR or \fIclass\fR,
then it is returned in the form of a Tk_Uid.  If multiple options
match \fIname\fR and \fIclass\fR, then the highest-priority one
is returned.  If no option matches, then NULL is returned.
.PP
\fBTk_GetOption\fR caches options related to \fItkwin\fR so that
successive calls for the same \fItkwin\fR will execute much more
quickly than successive calls for different windows.

.SH KEYWORDS
class, name, option, retrieve