'\" '\" Copyright (c) 1990 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_FreeXId 3 4.0 Tk "Tk Library Procedures" .so man.macros .BS .SH NAME Tk_FreeXId \- make X resource identifier available for reuse .SH SYNOPSIS .nf \fB#include \fR .sp \fBTk_FreeXId(\fIdisplay, id\fB)\fR .SH ARGUMENTS .AS Display *display out .AP Display *display in Display for which \fIid\fR was allocated. .AP XID id in Identifier of X resource (window, font, pixmap, cursor, graphics context, or colormap) that is no longer in use. .BE .SH DESCRIPTION .PP The default allocator for resource identifiers provided by Xlib is very simple-minded and does not allow resource identifiers to be re-used. If a long-running application reaches the end of the resource id space, it will generate an X protocol error and crash. Tk replaces the default id allocator with its own allocator, which allows identifiers to be reused. In order for this to work, \fBTk_FreeXId\fR must be called to tell the allocator about resources that have been freed. Tk automatically calls \fBTk_FreeXId\fR whenever it frees a resource, so if you use procedures like \fBTk_GetFont\fR, \fBTk_GetGC\fR, and \fBTk_GetPixmap\fR then you need not call \fBTk_FreeXId\fR. However, if you allocate resources directly from Xlib, for example by calling \fBXCreatePixmap\fR, then you should call \fBTk_FreeXId\fR when you call the corresponding Xlib free procedure, such as \fBXFreePixmap\fR. If you do not call \fBTk_FreeXId\fR then the resource identifier will be lost, which could cause problems if the application runs long enough to lose all of the available identifiers. .SH KEYWORDS resource identifier