table of contents
Tk_FreeXId(3) | Tk Library Procedures | Tk_FreeXId(3) |
NAME¶
Tk_FreeXId - make X resource identifier available for reuse
SYNOPSIS¶
#include <tk.h> Tk_FreeXId(display, id)
ARGUMENTS¶
- Display *display (in)
- Display for which id was allocated.
- XID id (in)
- Identifier of X resource (window, font, pixmap, cursor, graphics context,
or colormap) that is no longer in use.
DESCRIPTION¶
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, Tk_FreeXId must be called to tell the allocator about resources that have been freed. Tk automatically calls Tk_FreeXId whenever it frees a resource, so if you use procedures like Tk_GetFont, Tk_GetGC, and Tk_GetPixmap then you need not call Tk_FreeXId. However, if you allocate resources directly from Xlib, for example by calling XCreatePixmap, then you should call Tk_FreeXId when you call the corresponding Xlib free procedure, such as XFreePixmap. If you do not call Tk_FreeXId then the resource identifier will be lost, which could cause problems if the application runs long enough to lose all of the available identifiers.
KEYWORDS¶
resource identifier
4.0 | Tk |