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XInitThreads(3X11)
X11R6
NAME
  XInitThreads, XLockDisplay, XUnlockDisplay - multi-threading support

SYNOPSIS
  Status XInitThreads();

  void XLockDisplay(display)
	  Display *display;

  void XUnlockDisplay(display)
	  Display *display;

ARGUMENTS
  display
      Specifies the connection to the X server.

DESCRIPTION
  The XInitThreads function initializes Xlib support for concurrent threads.
  This function must be the first Xlib function a multi-threaded program
  calls, and it must complete before any other Xlib call is made. This
  function returns a nonzero status if initialization was successful;
  otherwise, it returns zero. On systems that do not support threads, this
  function always returns zero.

  It is only necessary to call this function if multiple threads might use
  Xlib concurrently.  If all calls to Xlib functions are protected by some
  other access mechanism (for example, a mutual exclusion lock in a toolkit
  or through explicit client programming), Xlib thread initialization is not
  required. It is recommended that single-threaded programs not call this
  function.

  The XLockDisplay function locks out all other threads from using the
  specified display. Other threads attempting to use the display will block
  until the display is unlocked by this thread. Nested calls to XLockDisplay
  work correctly; the display will not actually be unlocked until
  XUnlockDisplay has been called the same number of times as XLockDisplay.
  This function has no effect unless Xlib was successfully initialized for
  threads using XInitThreads.

  The XUnlockDisplay function allows other threads to use the specified
  display again. Any threads that have blocked on the display are allowed to
  continue. Nested locking works correctly; if XLockDisplay has been called
  multiple times by a thread, then XUnlockDisplay must be called an equal
  number of times before the display is actually unlocked. This function has
  no effect unless Xlib was successfully initialized for threads using
  XInitThreads.

SEE ALSO
  Xlib -- C Language X Interface

Index for Section 3X11

Alphabetical listing for X

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