Name:         GRGENV

Purpose:      get value of PGPLOT environment parameter

Category:     GRAPHICS

File:         pgplot.src

Author:       T.J. Pearson

Use:          see description below.

Description:

            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.

Updates:      Oct 16, 1998: JPT document extracted from 5.2.0 source;
                                Fortran source copied from GIPSY's v4.9E.