home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Tech Arsenal 1
/
Tech Arsenal (Arsenal Computer).ISO
/
tek-01
/
strlib.zip
/
GETOPT.C
< prev
next >
Wrap
Text File
|
1993-01-04
|
1KB
|
51 lines
/* File : getopt.c
Author : Henry Spencer, University of Toronto
Updated: 28 April 1984
Purpose: get option letter from argv.
*/
#include <stdio.h>
#include "strings.h"
char *optarg; /* Global argument pointer. */
int optind = 0; /* Global argv index. */
int getopt(argc, argv, optstring)
int argc;
char *argv[];
char *optstring;
{
register int c;
register char *place;
static char *scan = NullS; /* Private scan pointer. */
optarg = NullS;
if (scan == NullS || *scan == '\0') {
if (optind == 0) optind++;
if (optind >= argc) return EOF;
place = argv[optind];
if (place[0] != '-' || place[1] == '\0') return EOF;
optind++;
if (place[1] == '-' && place[2] == '\0') return EOF;
scan = place+1;
}
c = *scan++;
place = index(optstring, c);
if (place == NullS || c == ':') {
fprintf(stderr, "%s: unknown option %c\n", argv[0], c);
return '?';
}
if (*++place == ':') {
if (*scan != '\0') {
optarg = scan, scan = NullS;
} else {
optarg = argv[optind], optind++;
}
}
return c;
}