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-rw-r--r--src/lib/libc/stdlib/getopt.3315
1 files changed, 213 insertions, 102 deletions
diff --git a/src/lib/libc/stdlib/getopt.3 b/src/lib/libc/stdlib/getopt.3
index f843881afd..06167cb7d6 100644
--- a/src/lib/libc/stdlib/getopt.3
+++ b/src/lib/libc/stdlib/getopt.3
@@ -9,11 +9,7 @@
9.\" 2. Redistributions in binary form must reproduce the above copyright 9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the 10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution. 11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software 12.\" 3. Neither the name of the University nor the names of its contributors
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software 13.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission. 14.\" without specific prior written permission.
19.\" 15.\"
@@ -29,20 +25,20 @@
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE. 26.\" SUCH DAMAGE.
31.\" 27.\"
32.\" @(#)getopt.3 8.4 (Berkeley) 4/19/94 28.\" $OpenBSD: getopt.3,v 1.40 2007/05/31 19:19:31 jmc Exp $
33.\" 29.\"
34.Dd April 19, 1994 30.Dd $Mdocdate: May 31 2007 $
35.Dt GETOPT 3 31.Dt GETOPT 3
36.Os BSD 4.3 32.Os
37.Sh NAME 33.Sh NAME
38.Nm getopt 34.Nm getopt
39.Nd get option character from command line argument list 35.Nd get option character from command line argument list
40.Sh SYNOPSIS 36.Sh SYNOPSIS
41.Fd #include <unistd.h> 37.Fd #include <unistd.h>
42.Vt extern char *optarg; 38.Vt extern char *optarg;
39.Vt extern int opterr;
43.Vt extern int optind; 40.Vt extern int optind;
44.Vt extern int optopt; 41.Vt extern int optopt;
45.Vt extern int opterr;
46.Vt extern int optreset; 42.Vt extern int optreset;
47.Ft int 43.Ft int
48.Fn getopt "int argc" "char * const *argv" "const char *optstring" 44.Fn getopt "int argc" "char * const *argv" "const char *optstring"
@@ -61,20 +57,23 @@ if it has been specified in the string of accepted option characters,
61.Pp 57.Pp
62The option string 58The option string
63.Fa optstring 59.Fa optstring
64may contain the following elements: individual characters, and 60may contain the following elements: individual characters,
65characters followed by a colon to indicate an option argument 61characters followed by a colon, and characters followed by two colons.
66is to follow. 62A character followed by a single colon indicates that an argument
63is to follow the option on the command line.
64Two colons indicates that the argument is optional \- this is an
65extension not covered by POSIX.
67For example, an option string 66For example, an option string
68.Li "\&""x"" 67.Qq x
69recognizes an option 68recognizes an option
70.Dq Fl x , 69.Fl x ,
71and an option string 70and an option string
72.Li "\&""x:"" 71.Qq Li x:
73recognizes an option and argument 72recognizes an option and argument
74.Dq Fl x Ar argument . 73.Fl x Ar argument .
75It does not matter to 74It does not matter to
76.Fn getopt 75.Fn getopt
77if a following argument has leading white space. 76if a following argument has leading whitespace.
78.Pp 77.Pp
79On return from 78On return from
80.Fn getopt , 79.Fn getopt ,
@@ -87,23 +86,23 @@ contains the index to the next
87argument for a subsequent call 86argument for a subsequent call
88to 87to
89.Fn getopt . 88.Fn getopt .
90The variable
91.Va optopt
92saves the last
93.Em known
94option character returned by
95.Fn getopt .
96.Pp 89.Pp
97The variable 90The variables
98.Va opterr 91.Va opterr
99and 92and
100.Va optind 93.Va optind
101are both initialized to 1. 94are both initialized to 1.
102The 95The
103.Va optind 96.Va optind
104variable may be set to another value before a set of calls to 97variable may be set to another value larger than 0 before a set of calls to
105.Fn getopt 98.Fn getopt
106in order to skip over more or less argv entries. 99in order to skip over more or less
100.Fa argv
101entries.
102An
103.Va optind
104value of 0 is reserved for compatibility with GNU
105.Fn getopt .
107.Pp 106.Pp
108In order to use 107In order to use
109.Fn getopt 108.Fn getopt
@@ -119,101 +118,163 @@ must be reinitialized.
119.Pp 118.Pp
120The 119The
121.Fn getopt 120.Fn getopt
122function 121function returns \-1 when the argument list is exhausted.
123returns \-1
124when the argument list is exhausted, or a non-recognized
125option is encountered.
126The interpretation of options in the argument list may be cancelled 122The interpretation of options in the argument list may be cancelled
127by the option 123by the option
128.Ql -- 124.Ql --
129(double dash) which causes 125(double dash) which causes
130.Fn getopt 126.Fn getopt
131to signal the end of argument processing and returns \-1. 127to signal the end of argument processing and return \-1.
132When all options have been processed (i.e., up to the first non-option 128When all options have been processed (i.e., up to the first non-option
133argument), 129argument),
134.Fn getopt 130.Fn getopt
135returns \-1. 131returns \-1.
136.Sh DIAGNOSTICS 132.Sh RETURN VALUES
137If the 133The
138.Fn getopt 134.Fn getopt
139function encounters a character not found in the string 135function returns the next known option character in
140.Va optarg 136.Fa optstring .
141or detects
142a missing option argument it writes an error message and returns
143.Ql ?
144to the
145.Em stderr .
146Setting
147.Va opterr
148to a zero will disable these error messages.
149If 137If
150.Va optstring 138.Fn getopt
151has a leading 139encounters a character not found in
152.Ql \&: 140.Fa optstring
153then a missing option argument causes a 141or if it detects a missing option argument,
154.Ql \&: 142it returns
155to be returned in addition to suppressing any error messages. 143.Sq \&?
156.Pp 144(question mark).
157Option arguments are allowed to begin with 145If
158.Dq Li \- ; 146.Fa optstring
159this is reasonable but 147has a leading
160reduces the amount of error checking possible. 148.Sq \&:
161.Sh EXTENSIONS 149then a missing option argument causes
150.Sq \&:
151to be returned instead of
152.Sq \&? .
153In either case, the variable
154.Va optopt
155is set to the character that caused the error.
162The 156The
163.Va optreset
164variable was added to make it possible to call the
165.Fn getopt 157.Fn getopt
166function multiple times. 158function returns \-1 when the argument list is exhausted.
167This is an extension to the 159.Sh ENVIRONMENT
168.St -p1003.2 160.Bl -tag -width POSIXLY_CORRECTXX
169specification. 161.It Ev POSIXLY_CORRECT
170.Sh EXAMPLE 162If set, a leading
171.Bd -literal -compact 163.Sq -
172extern char *optarg; 164in
173extern int optind; 165.Ar optstring
166is ignored.
167.El
168.Sh EXAMPLES
169The following code accepts the options
170.Fl b
171and
172.Fl f Ar argument
173and adjusts
174.Va argc
175and
176.Va argv
177after option argument processing has completed.
178.Bd -literal -offset indent
174int bflag, ch, fd; 179int bflag, ch, fd;
175 180
176bflag = 0; 181bflag = 0;
177while ((ch = getopt(argc, argv, "bf:")) != -1) 182while ((ch = getopt(argc, argv, "bf:")) != -1) {
178 switch(ch) { 183 switch (ch) {
179 case 'b': 184 case 'b':
180 bflag = 1; 185 bflag = 1;
181 break; 186 break;
182 case 'f': 187 case 'f':
183 if ((fd = open(optarg, O_RDONLY, 0)) < 0) { 188 if ((fd = open(optarg, O_RDONLY, 0)) == -1)
184 (void)fprintf(stderr, 189 err(1, "%s", optarg);
185 "myname: %s: %s\en", optarg, strerror(errno));
186 exit(1);
187 }
188 break; 190 break;
189 case '?':
190 default: 191 default:
191 usage(); 192 usage();
193 /* NOTREACHED */
194 }
192} 195}
193argc -= optind; 196argc -= optind;
194argv += optind; 197argv += optind;
195.Ed 198.Ed
196.Sh HISTORY 199.Sh DIAGNOSTICS
200If the
201.Fn getopt
202function encounters a character not found in the string
203.Fa optstring
204or detects
205a missing option argument, it writes an error message to
206.Em stderr
207and returns
208.Ql \&? .
209Setting
210.Va opterr
211to a zero will disable these error messages.
212If
213.Fa optstring
214has a leading
215.Ql \&:
216then a missing option argument causes a
217.Ql \&:
218to be returned in addition to suppressing any error messages.
219.Pp
220Option arguments are allowed to begin with
221.Ql - ;
222this is reasonable but reduces the amount of error checking possible.
223.Sh SEE ALSO
224.Xr getopt 1 ,
225.Xr getopt_long 3 ,
226.Xr getsubopt 3
227.Sh STANDARDS
197The 228The
198.Fn getopt 229.Fn getopt
199function appeared 230function implements a superset of the functionality specified by
200.Bx 4.3 . 231.St -p1003.1 .
201.Sh BUGS 232.Pp
233The following extensions are supported:
234.Bl -tag -width "xxx"
235.It Li o
202The 236The
237.Va optreset
238variable was added to make it possible to call the
203.Fn getopt 239.Fn getopt
204function was once specified to return 240function multiple times.
205.Dv EOF 241.It Li o
206instead of \-1. 242If the
207This was changed by 243.Va optind
208.St -p1003.2-92 244variable is set to 0,
209to decouple
210.Fn getopt 245.Fn getopt
211from 246will behave as if the
212.Pa <stdio.h> . 247.Va optreset
213.Pp 248variable has been set.
249This is for compatibility with
250.Tn GNU
251.Fn getopt .
252New code should use
253.Va optreset
254instead.
255.It Li o
256If the first character of
257.Fa optstring
258is a plus sign
259.Pq Ql + ,
260it will be ignored.
261This is for compatibility with
262.Tn GNU
263.Fn getopt .
264.It Li o
265If the first character of
266.Fa optstring
267is a dash
268.Pq Ql - ,
269non-options will be returned as arguments to the option character
270.Ql \e1 .
271This is for compatibility with
272.Tn GNU
273.Fn getopt .
274.It Li o
214A single dash 275A single dash
215.Dq Li - 276.Pq Ql -
216may be specified as an character in 277may be specified as a character in
217.Fa optstring , 278.Fa optstring ,
218however it should 279however it should
219.Em never 280.Em never
@@ -221,40 +282,90 @@ have an argument associated with it.
221This allows 282This allows
222.Fn getopt 283.Fn getopt
223to be used with programs that expect 284to be used with programs that expect
224.Dq Li - 285.Ql -
225as an option flag. 286as an option flag.
226This practice is wrong, and should not be used in any current development. 287This practice is wrong, and should not be used in any current development.
227It is provided for backward compatibility 288It is provided for backward compatibility
228.Em only . 289.Em only .
290Care should be taken not to use
291.Ql -
292as the first character in
293.Fa optstring
294to avoid a semantic conflict with
295.Tn GNU
296.Fn getopt
297semantics (see above).
229By default, a single dash causes 298By default, a single dash causes
230.Fn getopt 299.Fn getopt
231to return \-1. 300to return \-1.
232This is, we believe, compatible with System V. 301.El
302.Pp
303Historic
304.Bx
305versions of
306.Fn getopt
307set
308.Fa optopt
309to the last option character processed.
310However, this conflicts with
311.St -p1003.1
312which stipulates that
313.Fa optopt
314be set to the last character that caused an error.
315.Sh HISTORY
316The
317.Fn getopt
318function appeared in
319.Bx 4.3 .
320.Sh BUGS
321The
322.Fn getopt
323function was once specified to return
324.Dv EOF
325instead of \-1.
326This was changed by
327.St -p1003.2-92
328to decouple
329.Fn getopt
330from
331.Aq Pa stdio.h .
233.Pp 332.Pp
234It is also possible to handle digits as option letters. 333It is possible to handle digits as option letters.
235This allows 334This allows
236.Fn getopt 335.Fn getopt
237to be used with programs that expect a number 336to be used with programs that expect a number
238.Pq Dq Li \&-\&3 337.Pq Dq Li \-3
239as an option. 338as an option.
240This practice is wrong, and should not be used in any current development. 339This practice is wrong, and should not be used in any current development.
241It is provided for backward compatibility 340It is provided for backward compatibility
242.Em only . 341.Em only .
243The following code fragment works in most cases. 342The following code fragment works in most cases and can handle mixed
343number and letter arguments.
244.Bd -literal -offset indent 344.Bd -literal -offset indent
245int length; 345int aflag = 0, bflag = 0, ch, lastch = '\e0';
246char *p; 346int length = -1, newarg = 1, prevoptind = 1;
247 347
248while ((c = getopt(argc, argv, "0123456789")) != -1) 348while ((ch = getopt(argc, argv, "0123456789ab")) != -1) {
249 switch (c) { 349 switch (ch) {
250 case '0': case '1': case '2': case '3': case '4': 350 case '0': case '1': case '2': case '3': case '4':
251 case '5': case '6': case '7': case '8': case '9': 351 case '5': case '6': case '7': case '8': case '9':
252 p = argv[optind - 1]; 352 if (newarg || !isdigit(lastch))
253 if (p[0] == '-' && p[1] == ch && !p[2]) 353 length = 0;
254 length = atoi(++p); 354 else if (length > INT_MAX / 10)
255 else 355 usage();
256 length = atoi(argv[optind] + 1); 356 length = (length * 10) + (ch - '0');
257 break; 357 break;
358 case 'a':
359 aflag = 1;
360 break;
361 case 'b':
362 bflag = 1;
363 break;
364 default:
365 usage();
258 } 366 }
367 lastch = ch;
368 newarg = optind != prevoptind;
369 prevoptind = optind;
259} 370}
260.Ed 371.Ed