NAME

       ncarg_gks - NCAR Graphics GKS Environment variables

SYNOPSIS

       A  collection  of  environment  variables  allows  you  to  control certain aspects of NCAR Graphics' GKS
       behaviour.

       NCARG_GKS_OUTPUT allows you to specify what file or process CGM output is directed to.

       NCARG_GKS_PSOUTPUT allows you to specify what file any PostScript output from NCAR  GKS  is  directed  to
       (stdout is allowed).

       NCARG_GKS_PDFOUTPUT  allows  you to specify what file any PDF output from NCAR GKS is directed to (stdout
       is allowed).

       NCARG_GKS_GENCGM allows you to request that the NCAR GKS package generate binary encoded CGM rather  than
       NCGM (the NCAR private encoding of binary encoded CGM).  Note that other NCAR Graphics utilities, such as
       the metafile translators, cannot read in generic CGM.

       NCARG_GKS_BUFSIZE provides you with control over how CGM output is buffered.

       NCARG_GKS_DEBUG, if set, will result in debugging information about the GKS I/O subsystem being output to
       standard out.

NCARG_GKS_OUTPUT

       By   default,   CGM  output  is  directed  to  a  file  called  "gmeta",  but  the  environment  variable
       NCARG_GKS_OUTPUT can be used to redirect output to a file with a different name or a translator process.

       Examples:

                 setenv NCARG_GKS_OUTPUT myfile

       causes CGM output to be placed in "myfile".

                 setenv NCARG_GKS_OUTPUT "|ctrans"

       causes the "ctrans" translator to be forked and CGM output piped to it.

                 setenv NCARG_GKS_OUTPUT "|"

       causes a default translator to be forked and CGM output to be piped to it. Note that not just any process
       can  be  used  here because it is assumed that the process is invoked as "translatorname -" where the "-"
       indicates that the translator is to read from standard input.

NCARG_GKS_PSOUTPUT

       By default, PostScript output is written to "gmetaNN.sfx"  where "NN" is the NCAR GKS workstation ID used
       in the call to GOPWK to open the workstation and "sfx" is "ps", "eps", or "epsi" as appropriate.  Setting
       NCARG_GKS_PSOUTPUT will override all defaults and write any PostScript output to the designated file.

       Examples:

                 setenv NCARG_GKS_PSOUTPUT myfile

       causes all PostScript output to be written to "myfile".

                 setenv NCARG_GKS_PSOUTPUT stdout

       causes all PostScript output to be written to standard out.

NCARG_GKS_PDFOUTPUT

       By default, PDF output is written to "gmetaNN.pdf"  where "NN" is the NCAR GKS workstation ID used in the
       call  to GOPWK to open the workstation.  Setting NCARG_GKS_PDFOUTPUT will override all defaults and write
       any PDF output to the designated file.

       Examples:

                 setenv NCARG_GKS_PDFOUTPUT myfile

       causes all PDF output to be written to "myfile".

                 setenv NCARG_GKS_PDFOUTPUT stdout

       causes all PDF output to be written to standard out.

NCARG_GKS_GENCGM

       If the NCARG_GKS_GENCGM environment variable is set, GKS will strip off the NCAR wrapper and  generate  a
       binary  encode  CGM.   As  mentioned  above,  other NCAR Graphics utilities such as translators don't yet
       support generic CGM as input. Thus, this option is useful primarily for getting CGM output  into  a  form
       appropriate for use with other software packages that expect binary encoded CGM.

       Example:

                 setenv NCARG_GKS_GENCGM

NCARG_GKS_BUFSIZE

       If  output  is  to  a  standard file, buffered I/O is used and the NCARG_GKS_BUFSIZE environment variable
       provides you with some flexibility in specifying buffer size.

       On Cray systems, the default buffer size is 1MB. All others  use  whatever  the  system  default  is,  as
       specified in the file "stdio.h".

       If  the environment variable NCARG_GKS_BUFSIZE is set, it overrides the defaults. If NCARG_GKS_BUFSIZE is
       set to N, behavior is as follows:

       If N is 0:

                 CGM output is unbuffered.

       If N is not 0:

                 Buffer Size = N * 1024 bytes.

       Examples

       Let's suppose you're running a long multi-frame graphics job on a Cray supercomputer and  you'd  like  to
       use a very large I/O buffer.  The default for a Cray is 1MB but you'd like to make it 2MB.

                 setenv NCARG_GKS_BUFSIZE 2048

       Now let's assume you're on the same Cray computer, but you want to pipe you're output to a translator and
       view the frames as they come up. A big buffer is a bad idea because your CGM might  not  be  flushed  out
       every frame. You can make the output unbuffered as follows:

                 setenv NCARG_GKS_OUTPUT "|ctrans"
                 setenv NCARG_GKS_BUFSIZE 0

       As  a  final  example,  let's  say  you're  running the big multi-frame NCAR Graphics job on a Sun, which
       happens to have a default buffer size of 1024 bytes (look in /usr/include/stdio.h). Specify a 1MB  buffer
       using:

                 setenv NCARG_GKS_BUFSIZE 1024

CAVEATS

       It's  worth  saying  one  more  time:  if you output binary encoded CGM rather than NCGM (NCAR CGM), NCAR
       Graphics generally won't deal with it.  The one exception is that you can convert the file back  to  NCGM
       using cgm2ncgm.

SEE ALSO

       cgm2ncgm(1NCARG), ncargintro(5NCARG), ncarg_env(5NCARG)

COPYRIGHT

       Copyright (C) 1987-2002
       University Corporation for Atmospheric Research
       The use of this Software is governed by a License Agreement.