64 lines
2.4 KiB
Groff
64 lines
2.4 KiB
Groff
'\"
|
|
'\" Copyright (c) 1990 The Regents of the University of California.
|
|
'\" All rights reserved.
|
|
'\"
|
|
'\" Permission is hereby granted, without written agreement and without
|
|
'\" license or royalty fees, to use, copy, modify, and distribute this
|
|
'\" documentation for any purpose, provided that the above copyright
|
|
'\" notice and the following two paragraphs appear in all copies.
|
|
'\"
|
|
'\" IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
|
|
'\" FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
|
|
'\" ARISING OUT OF THE USE OF THIS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
|
|
'\" CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
'\"
|
|
'\" THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
|
|
'\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
'\" AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
|
|
'\" ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
|
|
'\" PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
|
|
'\"
|
|
'\" $Header: /user6/ouster/wish/man/RCS/GetUid.3,v 1.5 93/04/01 09:41:40 ouster Exp $ SPRITE (Berkeley)
|
|
'\"
|
|
.so man.macros
|
|
.HS Tk_GetUid tkc
|
|
.BS
|
|
.SH NAME
|
|
Tk_GetUid, Tk_Uid \- convert from string to unique identifier
|
|
.SH SYNOPSIS
|
|
.nf
|
|
\fB#include <tk.h>\fR
|
|
.sp
|
|
\fB#typedef char *Tk_Uid\fR
|
|
.sp
|
|
Tk_Uid
|
|
\fBTk_GetUid\fR(\fIstring\fR)
|
|
.SH ARGUMENTS
|
|
.AP char *string in
|
|
String for which the corresponding unique identifer is
|
|
desired.
|
|
.BE
|
|
|
|
.SH DESCRIPTION
|
|
.PP
|
|
\fBTk_GetUid\fR returns the unique identifier corresponding
|
|
to \fIstring\fR.
|
|
Unique identifiers are similar to atoms in Lisp, and are used
|
|
in Tk to speed up comparisons and
|
|
searches. A unique identifier (type Tk_Uid) is a string pointer
|
|
and may be used anywhere that a variable of type ``char *''
|
|
could be used. However, there is guaranteed to be exactly
|
|
one unique identifier for any given string value. If \fBTk_GetUid\fR
|
|
is called twice, once with string \fIa\fR and once with string
|
|
\fIb\fR, and if \fIa\fR and \fIb\fR have the same string value
|
|
(strcmp(a, b) == 0), then \fBTk_GetUid\fR will return exactly
|
|
the same Tk_Uid value for each call (Tk_GetUid(a) == Tk_GetUid(b)).
|
|
This means that variables of type
|
|
Tk_Uid may be compared directly (x == y) without having to call
|
|
\fBstrcmp\fR.
|
|
In addition, the return value from \fBTk_GetUid\fR will have the
|
|
same string value as its argument (strcmp(Tk_GetUid(a), a) == 0).
|
|
|
|
.SH KEYWORDS
|
|
atom, unique identifier
|