<HTML><HEAD><TITLE>Tk Library Procedures - Tk_FreeXId manual page</TITLE></HEAD><BODY> <H3><A NAME="M2">NAME</A></H3> Tk_FreeXId - make X resource identifier available for reuse <H3><A NAME="M3">SYNOPSIS</A></H3> <B>#include <tk.h></B><BR> <B>Tk_FreeXId(</B><I>display, id</I><B>)</B><BR> <H3><A NAME="M4">ARGUMENTS</A></H3> <DL> <P><DT>Display <B>*display</B> (in)<DD> Display for which <I>id</I> was allocated. <P><DT>XID <B>id</B> (in)<DD> Identifier of X resource (window, font, pixmap, cursor, graphics context, or colormap) that is no longer in use. <P></DL> <H3><A NAME="M5">DESCRIPTION</A></H3> 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, <B>Tk_FreeXId</B> must be called to tell the allocator about resources that have been freed. Tk automatically calls <B>Tk_FreeXId</B> whenever it frees a resource, so if you use procedures like <B>Tk_GetFontStruct</B>, <B><A HREF="../TkLib/GetGC.htm">Tk_GetGC</A></B>, and <B><A HREF="../TkLib/GetPixmap.htm">Tk_GetPixmap</A></B> then you need not call <B>Tk_FreeXId</B>. However, if you allocate resources directly from Xlib, for example by calling <B>XCreatePixmap</B>, then you should call <B>Tk_FreeXId</B> when you call the corresponding Xlib free procedure, such as <B>XFreePixmap</B>. If you don't call <B>Tk_FreeXId</B> then the resource identifier will be lost, which could cause problems if the application runs long enough to lose all of the available identifiers. <H3><A NAME="M6">KEYWORDS</A></H3> <A href="../Keywords/R.htm#resource identifier">resource identifier</A> <HR><PRE> <A HREF="../copyright.htm">Copyright</A> © 1990 The Regents of the University of California. <A HREF="../copyright.htm">Copyright</A> © 1994-1996 Sun Microsystems, Inc. <A HREF="../copyright.htm">Copyright</A> © 1995-1997 Roger E. Critchlow Jr.</PRE> </BODY></HTML>