
/*
 * getenv - f77 subroutine to return environment variables
 *
 * called by:
 *	call getenv (ENV_NAME, char_var)
 * where:
 *	ENV_NAME is the name of an environment variable
 *	char_var is a character variable which will receive
 *		the current value of ENV_NAME, or all blanks
 *		if ENV_NAME is not defined
 */

#include <stdlib.h>
#include "f2c.h"

/* extern char **environ; */

#ifdef KR_headers
VOID getenv_(fname, value, flen, vlen) char *value, *fname; ftnlen vlen, flen;
#else
void getenv_(char *fname, char *value, ftnlen flen, ftnlen vlen)
#endif
{
  register char *ep, *fp, *flast;
  register char **env = environ;
  flast = fname + flen;
  for(fp = fname ; fp < flast ; ++fp)
    if(*fp == ' ')
      {
	flast = fp;
	break;
      }
  while ( (ep = *env++)) 
    {
      for(fp = fname; fp<flast ; )
	if(*fp++ != *ep++)
	  goto endloop;
      if(*ep++ == '=') {	/* copy right hand side */
	while( *ep && --vlen>=0 )
	  *value++ = *ep++;
	goto blank;
      }
    endloop: ;
    }
 blank:
  while( --vlen >= 0 )
    *value++ = ' ';
}
