Index for Section 3X11

Alphabetical listing for X

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XOpenDisplay(3X11)
X11R6
NAME
  XOpenDisplay, XCloseDisplay - connect or disconnect to X server

SYNOPSIS
  Display *XOpenDisplay(display_name)
	  char *display_name;

  XCloseDisplay(display)
	  Display *display;

ARGUMENTS
  display
      Specifies the connection to the X server.

  display_name
      Specifies the hardware display name, which determines the display and
      communications domain to be used. On a POSIX-conformant system, if the
      display_name is NULL, it defaults to the value of the DISPLAY
      environment variable.

DESCRIPTION
  The XOpenDisplay function returns a Display structure that serves as the
  connection to the X server and that contains all the information about that
  X server.  XOpenDisplay connects your application to the X server through
  TCP or DECnet communications protocols, or through some local inter-process
  communication protocol. If the hostname is a host machine name and a single
  colon (:) separates the hostname and display number, XOpenDisplay connects
  using TCP streams. If the hostname is not specified, Xlib uses whatever it
  believes is the fastest transport. If the hostname is a host machine name
  and a double colon (::) separates the hostname and display number,
  XOpenDisplay connects using DECnet. A single X server can support any or
  all of these transport mechanisms simultaneously. A particular Xlib
  implementation can support many more of these transport mechanisms.

  If successful, XOpenDisplay returns a pointer to a Display structure, which
  is defined in <X11/Xlib.h>. If XOpenDisplay does not succeed, it returns
  NULL. After a successful call to XOpenDisplay, all of the screens in the
  display can be used by the client. The screen number specified in the
  display_name argument is returned by the DefaultScreen macro (or the
  XDefaultScreen function).  You can access elements of the Display and
  Screen structures only by using the information macros or functions.	For
  information about using macros and functions to obtain information from the
  Display structure, see section 2.2.1.

  The XCloseDisplay function closes the connection to the X server for the
  display specified in the Display structure and destroys all windows,
  resource IDs (Window, Font, Pixmap, Colormap, Cursor, and GContext), or
  other resources that the client has created on this display, unless the
  close-down mode of the resource has been changed (see XSetCloseDownMode).
  Therefore, these windows, resource IDs, and other resources should never be
  referenced again or an error will be generated. Before exiting, you should
  call XCloseDisplay explicitly so that any pending errors are reported as
  XCloseDisplay performs a final XSync operation.

  XCloseDisplay can generate a BadGC error.

SEE ALSO
  AllPlanes(3X11), XFlush(3X11), XSetCloseDownMode(3X11)

  Xlib -- C Language X Interface

Index for Section 3X11

Alphabetical listing for X

Top of page