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.