Tk_GetUid(3) Tk Library Procedures Tk_GetUid(3)
NAME
Tk_GetUid, Tk_Uid - convert from string to unique identifier
SYNOPSIS
#include <tk.h>
Tk_Uid
Tk_GetUid(string)
ARGUMENTS
String for which the corresponding unique identifier is desired.
DESCRIPTION
Tk_GetUid returns the unique identifier corresponding to string.
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
could be used. However, there is guaranteed to be exactly one unique
identifier for any given string value. If Tk_GetUid is called twice,
once with string a and once with string b, and if a and b have the same
string value (strcmp(a, b) == 0), then Tk_GetUid 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 strcmp. In addition, the return value from
Tk_GetUid will have the same string value as its argument (str-
cmp(Tk_GetUid(a), a) == 0).
KEYWORDS
atom, unique identifier
Tk Tk_GetUid(3)
GetUid 8.5.4 - Generated Sat Aug 23 18:48:58 CDT 2008