XkbOpenDisplay(3)         XKB FUNCTIONS         XkbOpenDisplay(3)



NAME
       XkbOpenDisplay  -   Checks for a compatible version of the
       Xkb extension in both the library and the server, and ini-
       tializes the extension for use.

SYNOPSIS
       Display   XkbOpenDisplay   (   display_name,   event_rtrn,
       error_rtrn, major_in_out, minor_in_out, reason_rtrn )
             char *display_name;
             int *event_rtrn;
             int *error_rtrn;
             int *major_in_out;
             int *minor_in_out;
             int *reason_rtrn;

ARGUMENTS
       display_name
              hardware display name, which determines the display
              and communications domain to be used

       event_rtrn
              backfilled with the extension base event code

       error_rtrn
              backfilled with the extension base error code

       major_in_out
              compile  time  lib  major  version in, server major
              version out

       minor_in_out
              compile time lib min version in, server minor  ver-
              sion out

       reason_rtrn
              backfilled with a status code

DESCRIPTION
       As  a convenience, you can use the function XkbOpenDisplay
       to perform these three tasks at once: open a connection to
       an  X  server,  check  for a compatible version of the Xkb
       extension in both the library and the server, and initial-
       ize the extension for use.

       XkbOpenDisplay  is  a convenience function that opens an X
       display connection and initializes the X  keyboard  exten-
       sion.  In  all  cases,  upon return reason_rtrn contains a
       status value indicating success or the type of failure. If
       major_in_out and minor_in_out are not NULL, XkbOpenDisplay
       first calls XkbLibraryVersion  to  determine  whether  the
       client  library  is  compatible,  passing  it  the  values
       pointed  to  by  major_in_out  and  minor_in_out.  If  the
       library    is   incompatible,   XkbOpenDisplay   backfills
       major_in_out and minor_in_out with  the  major  and  minor
       extension  versions  of the library being used and returns
       NULL.  If the library is compatible,  XkbOpenDisplay  next
       calls  XOpenDisplay with the display_name.  If this fails,
       the function returns NULL. If  successful,  XkbOpenDisplay
       calls  XkbQueryExtension and backfills the major and minor
       Xkb server extension version numbers in  major_in_out  and
       minor_in_out.  If the server extension version is not com-
       patible with the  library  extension  version  or  if  the
       server extension is not present, XkbOpenDisplay closes the
       display and returns NULL. When  successful,  the  function
       returns the display connection.

       The possible values for reason_rtrn are:


       o    XkbOD_BadLibraryVersion  indicates  XkbLibraryVersion
            returned False.

       o    XkbOD_ConnectionRefused indicates the  display  could
            not be opened.

       o    XkbOD_BadServerVersion  indicates the library and the
            server have incompatible extension versions.

       o    XkbOD_NonXkbServer indicates  the  extension  is  not
            present in the X server.

       o    XkbOD_Success  indicates that the function succeeded.

RETURN VALUES
       NULL           The XkbOpenDisplay function returns NULL if
                      the library is incompatible.

                    The  XkbOpenDisplay  function returns NULL if
                    the  call  to  XOpenDisplay  with  the   dis-
                    play_name fails.

                    The  XkbOpenDisplay function returns NULL and
                    closes the display if  the  server  extension
                    version  is  not  compatible with the library
                    extension version or if the server  extension
                    is not present.

DIAGNOSTICS
       BadAccess      The  Xkb  extension  has  not been properly
                      initialized

SEE ALSO
       XkbLibraryVersion(3),   XkbQueryExtension(3),    XOpenDis-
       play(3X11)



X Version 11               libX11 1.1.5         XkbOpenDisplay(3)