hpux man page for xdisplayname

XDisplayName()															    XDisplayName()

Name
  XDisplayName - report the display name (when connection to a display fails).

Synopsis
  char *XDisplayName(string)
	char *string;

Arguments
  string    Specifies the character string.

Returns
  The display name string.

Description
  XDisplayName()  is  normally	used  to report the name of the display the program attempted to open with XOpenDisplay().  This is necessary
  because X error handling begins only after the connection to the server succeeds.

  If a NULL string is specified, XDisplayName() looks in the DISPLAY environment variable and returns the display  name  that  the  user  was
  requesting.  Otherwise, XDisplayName() returns its own argument.

  For more information, see Volume One, Chapter 3, Basic Window Program.

See Also
  XGetErrorDatabaseText(), XGetErrorText(), XSetAfterFunction(), XSetErrorHandler(), XSetIOErrorHandler(), XSynchronize().

Xlib - Error Handling														    XDisplayName()