NAME

       gesc - Provide "Escape" for non-standard GKS features

DESCRIPTION

       GESC  (Escape) - provides a standard way of implementing nonstandard GKS features.  NCAR GKS has only two
       user-accessible escape functions defined: one for changing the name of a metafile and another for pausing
       in an X window.

SYNOPSIS

       CALL GESC (FCTID, LIDR, IDR, MXODR, LODR, ODR)

C-BINDING SYNOPSIS

       #include <ncarg/gks.h>

       void  gescape(Gint  func_id,  const   Gescape_in_data   *in_data,   Gstore   *store_data,Gescape_out_data
       **out_data);

DESCRIPTION

       FCTID       (Integer, Input) - A function identifier specifying the requested activity.  The legal values
                   for  FCTID are "-1391" for changing a metafile name and "-1396" for effecting a pause in an X
                   window.

       LIDR        (Integer, Input) - Dimension of the IDR input data record array (for IDR, see below).

       IDR         (Character * 80 Array, Input) - Input data record.  For calls to GESC  with  FCTID  equal  to
                   -1391 the input data record should contain the desired metafile name left justified and blank
                   filled;  for calls to GESC with FCTID equal to -1396 the input data record should contain the
                   workstation identifier encoded as a five character number.

       MXODR       (Integer, Input) - Maximum length of the ODR output data record array (for ODR, see below).

       LODR        (Integer, Output) - Dimension of the ODR output data record array.

       ODR (MXODR) (Character * 80 Array, Output) -  Output data record.

USAGE

       LIDR, MXODR, and LODR must always be at least "1" in value.

EXAMPLES

       GESC can be used to dynamically change the name of an output metafile and to do so  one  should  use  the
       calls  GOPKS  and  GOPWK  instead  of  OPNGKS.   If you are using OPNGKS, see the man page for SETUSV for
       changing the name of the metafile.

       To change the name of the output metafile inside your program, you should make  a  call  similar  to  the
       following:

              CHARACTER*80 MFNAME

              CALL GOPKS (6,IDUM)
              MFNAME = 'new.cgm.name'
              CALL GESC(-1391,1,MFNAME,1,1,CDUM)

       The call to GESC to change the metafile name must always occur just before the call to GOPWK that opens a
       CGM  workstation.   Setting the environment variable NCARG_GKS_OUTPUT overrides any attempt to change the
       name of an output metafile via a GESC call.

       See the "User's Guide for NCAR GKS-0A Graphics" for a more complete example of  changing  metafile  names
       from within a code.

       Here  is  an  example  of  a code that will create an X window, draw a line, and then pause waiting for a
       mouse click or a key click.

              CHARACTER*80 IREC,ODUM
              CALL GOPKS(6,0)
              CALL GOPWK(3,0,8)
              CALL GACWK(3)
              CALL LINE(0.,0.,1.,1.)
              CALL SFLUSH
              IREC = '    3'
              CALL GESC(-1396,1,IREC,1,1,ODUM)
              CALL GDAWK(3)
              CALL GCLWK(3)
              CALL GCLKS
              STOP
              END

       The functions FRAME and NGPICT are in general much easier to use and more flexible than the direct ESCAPE
       call for pausing in an X window.  It is suggested that those functions be used.

ACCESS

       To use GKS routines, load the NCAR GKS-0A library ncarg_gks.

SEE ALSO

       Online: SETUSV, FRAME, NGPICT, gescape

       Hardcopy: User's Guide for NCAR GKS-0A Graphics; NCAR Graphics Fundamentals, UNIX Version

COPYRIGHT

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research
       The use of this Software is governed by a License Agreement.

UNIX                                               March 1993                                       GESC(3NCARG)