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--- Libc/Libc-320/stdlib/FreeBSD/getopt.3
+++ Libc/Libc-583/stdlib/FreeBSD/getopt.3
@@ -1,3 +1,5 @@
+.\" $NetBSD: getopt.3,v 1.31 2003/09/23 10:26:54 wiz Exp $
+.\"
.\" Copyright (c) 1988, 1991, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
@@ -30,7 +32,7 @@
.\" SUCH DAMAGE.
.\"
.\" @(#)getopt.3 8.5 (Berkeley) 4/27/95
-.\" $FreeBSD: src/lib/libc/stdlib/getopt.3,v 1.21 2002/12/04 18:57:45 ru Exp $
+.\" $FreeBSD: src/lib/libc/stdlib/getopt.3,v 1.25 2004/07/31 01:00:50 imp Exp $
.\"
.Dd April 27, 1995
.Dt GETOPT 3
@@ -43,12 +45,12 @@
.Sh SYNOPSIS
.In unistd.h
.Vt extern char *optarg ;
-.Vt extern int optind ;
-.Vt extern int optopt ;
-.Vt extern int opterr ;
-.Vt extern int optreset ;
+.Vt extern int optind ;
+.Vt extern int optopt ;
+.Vt extern int opterr ;
+.Vt extern int optreset ;
.Ft int
-.Fn getopt "int argc" "char * const *argv" "const char *optstring"
+.Fn getopt "int argc" "char * const argv[]" "const char *optstring"
.Sh DESCRIPTION
The
.Fn getopt
@@ -97,7 +99,7 @@
option character returned by
.Fn getopt .
.Pp
-The variable
+The variables
.Va opterr
and
.Va optind
@@ -122,12 +124,7 @@
.Pp
The
.Fn getopt
-function
-returns \-1
-when the argument list is exhausted, or
-.Ql ?\&
-if a non-recognized
-option is encountered.
+function returns \-1 when the argument list is exhausted.
The interpretation of options in the argument list may be cancelled
by the option
.Ql --
@@ -138,21 +135,74 @@
argument),
.Fn getopt
returns \-1.
+.Sh RETURN VALUES
+The
+.Fn getopt
+function returns the next known option character in
+.Fa optstring .
+If
+.Fn getopt
+encounters a character not found in
+.Fa optstring
+or if it detects a missing option argument,
+it returns
+.Ql \&?
+(question mark).
+If
+.Fa optstring
+has a leading
+.Ql \&:
+then a missing option argument causes
+.Ql \&:
+to be returned instead of
+.Ql \&? .
+In either case, the variable
+.Va optopt
+is set to the character that caused the error.
+The
+.Fn getopt
+function returns \-1 when the argument list is exhausted.
+.Sh EXAMPLES
+.Bd -literal -compact
+#include <unistd.h>
+int bflag, ch, fd;
+
+bflag = 0;
+while ((ch = getopt(argc, argv, "bf:")) != -1) {
+ switch (ch) {
+ case 'b':
+ bflag = 1;
+ break;
+ case 'f':
+ if ((fd = open(optarg, O_RDONLY, 0)) \*[Lt] 0) {
+ (void)fprintf(stderr,
+ "myname: %s: %s\en", optarg, strerror(errno));
+ exit(1);
+ }
+ break;
+ case '?':
+ default:
+ usage();
+ }
+}
+argc -= optind;
+argv += optind;
+.Ed
.Sh DIAGNOSTICS
If the
.Fn getopt
function encounters a character not found in the string
-.Va optstring
+.Fa optstring
or detects
a missing option argument it writes an error message to the
.Dv stderr
and returns
-.Ql ?\& .
+.Ql \&? .
Setting
.Va opterr
to a zero will disable these error messages.
If
-.Va optstring
+.Fa optstring
has a leading
.Ql \&:
then a missing option argument causes a
@@ -161,9 +211,12 @@
.Pp
Option arguments are allowed to begin with
.Dq Li \- ;
-this is reasonable but
-reduces the amount of error checking possible.
-.Sh EXTENSIONS
+this is reasonable but reduces the amount of error checking possible.
+.Sh SEE ALSO
+.Xr getopt 1 ,
+.Xr getopt_long 3 ,
+.Xr getsubopt 3
+.Sh STANDARDS
The
.Va optreset
variable was added to make it possible to call the
@@ -172,27 +225,6 @@
This is an extension to the
.St -p1003.2
specification.
-.Sh EXAMPLES
-.Bd -literal -compact
-int bflag, ch, fd;
-
-bflag = 0;
-while ((ch = getopt(argc, argv, "bf:")) != -1)
- switch (ch) {
- case 'b':
- bflag = 1;
- break;
- case 'f':
- if ((fd = open(optarg, O_RDONLY, 0)) < 0)
- err(1, "%s", optarg);
- break;
- case '?':
- default:
- usage();
- }
-argc -= optind;
-argv += optind;
-.Ed
.Sh HISTORY
The
.Fn getopt
@@ -209,7 +241,7 @@
to decouple
.Fn getopt
from
-.Pa <stdio.h> .
+.In stdio.h .
.Pp
A single dash
.Dq Li -
@@ -226,10 +258,20 @@
This practice is wrong, and should not be used in any current development.
It is provided for backward compatibility
.Em only .
+Care should be taken not to use
+.Ql \&-
+as the first character in
+.Fa optstring
+to avoid a semantic conflict with
+.Tn GNU
+.Fn getopt ,
+which assigns different meaning to an
+.Fa optstring
+that begins with a
+.Ql \&- .
By default, a single dash causes
.Fn getopt
to return \-1.
-This is, we believe, compatible with System V.
.Pp
It is also possible to handle digits as option letters.
This allows
@@ -240,9 +282,10 @@
This practice is wrong, and should not be used in any current development.
It is provided for backward compatibility
.Em only .
-The following code fragment works in most (but not all) cases.
+The following code fragment works in most cases.
.Bd -literal -offset indent
-int length;
+int ch;
+long length;
char *p, *ep;
while ((ch = getopt(argc, argv, "0123456789")) != -1)
@@ -250,16 +293,17 @@
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
p = argv[optind - 1];
- if (p[0] == '-' && p[1] == ch && !p[2])
- length = strtol(++p, &ep, 10);
- else if (argv[optind] && argv[optind][1] == ch) {
+ if (p[0] == '-' \*[Am]\*[Am] p[1] == ch \*[Am]\*[Am] !p[2]) {
+ length = ch - '0';
+ ep = "";
+ } else if (argv[optind] \*[Am]\*[Am] argv[optind][1] == ch) {
length = strtol((p = argv[optind] + 1),
- &ep, 10);
+ \*[Am]ep, 10);
optind++;
optreset = 1;
} else
usage();
- if (*ep != '\0')
+ if (*ep != '\e0')
errx(EX_USAGE, "illegal number -- %s", p);
break;
}