
NAME
	  getopt - get option letter from argument vector
SYNTAX
	  int getopt (argc, argv, optstring)
	  int argc;
	  char **argv, *opstring;
	  extern char *optarg;
	  extern int optind, opterr;
DESCRIPTION
	  Getopt returns the next option letter	in argv	that matches a
	  letter in optstring.	Optstring is a string of recognized
	  option letters; if a letter is followed by a colon, the
	  option is expected to	have an	argument that may or may not
	  be separated from it by white	space.	Optarg is set to point
	  to the start of the option argument on return	from getopt.
	  Getopt places	in optind the argv index of the	next argument
	  to be	processed.  Because optind is external,	it is normally
	  initialized to zero automatically before the first call to
	  getopt.
	  When all options have	been processed (i.e., up to the	first
	  non-option argument),	getopt returns EOF.  The special
	  option -- may	be used	to delimit the end of the options; EOF
	  will be returned, and	-- will	be skipped.
DIAGNOSTICS
	  Getopt prints	an error message on stderr and returns a
	  question mark	(?)  when it encounters	an option letter not
	  included in optstring.  This error message may be disabled
	  by setting opterr to a non-zero value.
     EXAMPLE
	  The following	code fragment shows how	one might process the
	  arguments for	a command that can take	the mutually exclusive
	  options a and	b, and the options f and o, both of which
	  require arguments:
	       main (argc, argv)
	       int argc;
	       char **argv;
	       {
		    int	c;
		    extern char	*optarg;
		    extern int optind;
		    .
		    .
		    .
		    while ((c =	getopt(argc, argv, "abf:o:")) != EOF)
				  
			 switch	(c) {
			 case 'a':
			      if (bflg)
				   errflg++;
			      else
				   aflg++;
			      break;
			 case 'b':
			      if (aflg)
				   errflg++;
			      else
				   bproc( );
			      break;
			 case 'f':
			      ifile = optarg;
			      break;
			 case 'o':
			      ofile = optarg;
			      break;
			 case '?':
			      errflg++;
			 }
		    if (errflg)	{
			 fprintf(stderr, "usage: . . . ");
			 exit (2);
		    }
		    for	( ; optind < argc; optind++) {
			 if (access(argv[optind], 4)) {
		    .
		    .
		    .
	       }
SEE ALSO
	  getopt(1) in the UNIX	System V User Reference	Manual.
 
