%N grgenv %F $MIR/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_science_miriad/miriad/work/miriad-4.3.8/borrow/pgplot/sys/grgenv.f
%D Get value of PGPLOT environment parameter (Sun/Convex-UNIX)
%B
      SUBROUTINE GRGENV(NAME, VALUE, L)
      CHARACTER*(*) NAME, VALUE
      INTEGER L

 Return the value of a PGPLOT environment parameter. In Sun/Convex-UNIX,
 environment parameters are UNIX environment variables; e.g. parameter
 ENVOPT is environment variable PGPLOT_ENVOPT. Translation is not
 recursive and is case-sensitive.

 Arguments:
  NAME   : (input) the name of the parameter to evaluate.
  VALUE  : receives the value of the parameter, truncated or extended
           with blanks as necessary. If the parameter is undefined,
           a blank string is returned.
  L      : receives the number of characters in VALUE, excluding
           trailing blanks. If the parameter is undefined, zero is
           returned.
