diff options
Diffstat (limited to 'src/lib/libc/stdlib/getopt.3')
-rw-r--r-- | src/lib/libc/stdlib/getopt.3 | 252 |
1 files changed, 166 insertions, 86 deletions
diff --git a/src/lib/libc/stdlib/getopt.3 b/src/lib/libc/stdlib/getopt.3 index f843881afd..d210852c6b 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 | .\" |
@@ -29,11 +25,11 @@ | |||
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 1.28 2003/09/22 23:47:26 millert Exp $ |
33 | .\" | 29 | .\" |
34 | .Dd April 19, 1994 | 30 | .Dd December 17, 2002 |
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 |
@@ -61,20 +57,24 @@ if it has been specified in the string of accepted option characters, | |||
61 | .Pp | 57 | .Pp |
62 | The option string | 58 | The option string |
63 | .Fa optstring | 59 | .Fa optstring |
64 | may contain the following elements: individual characters, and | 60 | may contain the following elements: individual characters, |
65 | characters followed by a colon to indicate an option argument | 61 | characters followed by a colon, and characters followed by two colons. |
66 | is to follow. | 62 | A character followed by a single colon indicates that an argument |
63 | is to follow the option on the command line. | ||
64 | Two colons indicates that the argument is optional--this is an | ||
65 | extension not covered by | ||
66 | .Px . | ||
67 | For example, an option string | 67 | For example, an option string |
68 | .Li "\&""x"" | 68 | .Qq x |
69 | recognizes an option | 69 | recognizes an option |
70 | .Dq Fl x , | 70 | .Fl x , |
71 | and an option string | 71 | and an option string |
72 | .Li "\&""x:"" | 72 | .Qq Li x: |
73 | recognizes an option and argument | 73 | recognizes an option and argument |
74 | .Dq Fl x Ar argument . | 74 | .Fl x Ar argument . |
75 | It does not matter to | 75 | It does not matter to |
76 | .Fn getopt | 76 | .Fn getopt |
77 | if a following argument has leading white space. | 77 | if a following argument has leading whitespace. |
78 | .Pp | 78 | .Pp |
79 | On return from | 79 | On return from |
80 | .Fn getopt , | 80 | .Fn getopt , |
@@ -87,14 +87,8 @@ contains the index to the next | |||
87 | argument for a subsequent call | 87 | argument for a subsequent call |
88 | to | 88 | to |
89 | .Fn getopt . | 89 | .Fn getopt . |
90 | The variable | ||
91 | .Va optopt | ||
92 | saves the last | ||
93 | .Em known | ||
94 | option character returned by | ||
95 | .Fn getopt . | ||
96 | .Pp | 90 | .Pp |
97 | The variable | 91 | The variables |
98 | .Va opterr | 92 | .Va opterr |
99 | and | 93 | and |
100 | .Va optind | 94 | .Va optind |
@@ -119,63 +113,62 @@ must be reinitialized. | |||
119 | .Pp | 113 | .Pp |
120 | The | 114 | The |
121 | .Fn getopt | 115 | .Fn getopt |
122 | function | 116 | function returns \-1 when the argument list is exhausted. |
123 | returns \-1 | ||
124 | when the argument list is exhausted, or a non-recognized | ||
125 | option is encountered. | ||
126 | The interpretation of options in the argument list may be cancelled | 117 | The interpretation of options in the argument list may be cancelled |
127 | by the option | 118 | by the option |
128 | .Ql -- | 119 | .Ql -- |
129 | (double dash) which causes | 120 | (double dash) which causes |
130 | .Fn getopt | 121 | .Fn getopt |
131 | to signal the end of argument processing and returns \-1. | 122 | to signal the end of argument processing and return \-1. |
132 | When all options have been processed (i.e., up to the first non-option | 123 | When all options have been processed (i.e., up to the first non-option |
133 | argument), | 124 | argument), |
134 | .Fn getopt | 125 | .Fn getopt |
135 | returns \-1. | 126 | returns \-1. |
136 | .Sh DIAGNOSTICS | 127 | .Sh RETURN VALUES |
137 | If the | 128 | The |
138 | .Fn getopt | 129 | .Fn getopt |
139 | function encounters a character not found in the string | 130 | function returns the next known option character in |
140 | .Va optarg | 131 | .Fa optstring . |
141 | or detects | ||
142 | a missing option argument it writes an error message and returns | ||
143 | .Ql ? | ||
144 | to the | ||
145 | .Em stderr . | ||
146 | Setting | ||
147 | .Va opterr | ||
148 | to a zero will disable these error messages. | ||
149 | If | 132 | If |
150 | .Va optstring | 133 | .Fn getopt |
151 | has a leading | 134 | encounters a character not found in |
152 | .Ql \&: | 135 | .Fa optstring |
153 | then a missing option argument causes a | 136 | or if it detects a missing option argument, |
154 | .Ql \&: | 137 | it returns |
155 | to be returned in addition to suppressing any error messages. | 138 | .Sq \&? |
156 | .Pp | 139 | (question mark). |
157 | Option arguments are allowed to begin with | 140 | If |
158 | .Dq Li \- ; | 141 | .Fa optstring |
159 | this is reasonable but | 142 | has a leading |
160 | reduces the amount of error checking possible. | 143 | .Sq \&: |
161 | .Sh EXTENSIONS | 144 | then a missing option argument causes |
145 | .Sq \&: | ||
146 | to be returned instead of | ||
147 | .Sq \&? . | ||
148 | In either case, the variable | ||
149 | .Va optopt | ||
150 | is set to the character that caused the error. | ||
162 | The | 151 | The |
163 | .Va optreset | ||
164 | variable was added to make it possible to call the | ||
165 | .Fn getopt | 152 | .Fn getopt |
166 | function multiple times. | 153 | function returns \-1 when the argument list is exhausted. |
167 | This is an extension to the | 154 | .Sh ENVIRONMENT |
168 | .St -p1003.2 | 155 | .Bl -tag -width POSIXLY_CORRECTXX |
169 | specification. | 156 | .It Ev POSIXLY_CORRECT |
170 | .Sh EXAMPLE | 157 | If set, a leading |
158 | .Sq - | ||
159 | in | ||
160 | .Ar optstring | ||
161 | is ignored. | ||
162 | .El | ||
163 | .Sh EXAMPLES | ||
171 | .Bd -literal -compact | 164 | .Bd -literal -compact |
172 | extern char *optarg; | 165 | extern char *optarg; |
173 | extern int optind; | 166 | extern int optind; |
174 | int bflag, ch, fd; | 167 | int bflag, ch, fd; |
175 | 168 | ||
176 | bflag = 0; | 169 | bflag = 0; |
177 | while ((ch = getopt(argc, argv, "bf:")) != -1) | 170 | while ((ch = getopt(argc, argv, "bf:")) != -1) { |
178 | switch(ch) { | 171 | switch (ch) { |
179 | case 'b': | 172 | case 'b': |
180 | bflag = 1; | 173 | bflag = 1; |
181 | break; | 174 | break; |
@@ -189,31 +182,76 @@ while ((ch = getopt(argc, argv, "bf:")) != -1) | |||
189 | case '?': | 182 | case '?': |
190 | default: | 183 | default: |
191 | usage(); | 184 | usage(); |
185 | } | ||
192 | } | 186 | } |
193 | argc -= optind; | 187 | argc -= optind; |
194 | argv += optind; | 188 | argv += optind; |
195 | .Ed | 189 | .Ed |
196 | .Sh HISTORY | 190 | .Sh DIAGNOSTICS |
197 | The | 191 | If the |
198 | .Fn getopt | 192 | .Fn getopt |
199 | function appeared | 193 | function encounters a character not found in the string |
200 | .Bx 4.3 . | 194 | .Fa optstring |
201 | .Sh BUGS | 195 | or detects |
196 | a missing option argument it writes an error message to | ||
197 | .Em stderr | ||
198 | and returns | ||
199 | .Ql \&? . | ||
200 | Setting | ||
201 | .Va opterr | ||
202 | to a zero will disable these error messages. | ||
203 | If | ||
204 | .Fa optstring | ||
205 | has a leading | ||
206 | .Ql \&: | ||
207 | then a missing option argument causes a | ||
208 | .Ql \&: | ||
209 | to be returned in addition to suppressing any error messages. | ||
210 | .Pp | ||
211 | Option arguments are allowed to begin with | ||
212 | .Ql - ; | ||
213 | this is reasonable but reduces the amount of error checking possible. | ||
214 | .Sh SEE ALSO | ||
215 | .Xr getopt 1 , | ||
216 | .Xr getopt_long 3 , | ||
217 | .Xr getsubopt 3 | ||
218 | .Sh STANDARDS | ||
202 | The | 219 | The |
203 | .Fn getopt | 220 | .Fn getopt |
204 | function was once specified to return | 221 | function implements a superset of the functionality specified by |
205 | .Dv EOF | 222 | .St -p1003.1 . |
206 | instead of \-1. | ||
207 | This was changed by | ||
208 | .St -p1003.2-92 | ||
209 | to decouple | ||
210 | .Fn getopt | ||
211 | from | ||
212 | .Pa <stdio.h> . | ||
213 | .Pp | 223 | .Pp |
224 | The following extensions are supported: | ||
225 | .Bl -tag -width "xxx" | ||
226 | .It Li o | ||
227 | The | ||
228 | .Va optreset | ||
229 | variable was added to make it possible to call the | ||
230 | .Fn getopt | ||
231 | function multiple times. | ||
232 | .It Li o | ||
233 | If the first character of | ||
234 | .Fa optstring | ||
235 | is a plus sign | ||
236 | .Pq Ql + , | ||
237 | it will be ignored. | ||
238 | This is for compatibility with | ||
239 | .Tn GNU | ||
240 | .Fn getopt . | ||
241 | .It Li o | ||
242 | If the first character of | ||
243 | .Fa optstring | ||
244 | is a dash | ||
245 | .Pq Ql - , | ||
246 | non-options will be returned as arguments to the option character | ||
247 | .Ql \e1 . | ||
248 | This is for compatibility with | ||
249 | .Tn GNU | ||
250 | .Fn getopt . | ||
251 | .It Li o | ||
214 | A single dash | 252 | A single dash |
215 | .Dq Li - | 253 | .Pq Ql - |
216 | may be specified as an character in | 254 | may be specified as a character in |
217 | .Fa optstring , | 255 | .Fa optstring , |
218 | however it should | 256 | however it should |
219 | .Em never | 257 | .Em never |
@@ -221,39 +259,81 @@ have an argument associated with it. | |||
221 | This allows | 259 | This allows |
222 | .Fn getopt | 260 | .Fn getopt |
223 | to be used with programs that expect | 261 | to be used with programs that expect |
224 | .Dq Li - | 262 | .Ql - |
225 | as an option flag. | 263 | as an option flag. |
226 | This practice is wrong, and should not be used in any current development. | 264 | This practice is wrong, and should not be used in any current development. |
227 | It is provided for backward compatibility | 265 | It is provided for backward compatibility |
228 | .Em only . | 266 | .Em only . |
267 | Care should be taken not to use | ||
268 | .Ql - | ||
269 | as the first character in | ||
270 | .Fa optstring | ||
271 | to avoid a semantic conflict with | ||
272 | .Tn GNU | ||
273 | .Fn getopt | ||
274 | semantics (see above). | ||
229 | By default, a single dash causes | 275 | By default, a single dash causes |
230 | .Fn getopt | 276 | .Fn getopt |
231 | to return \-1. | 277 | to return \-1. |
232 | This is, we believe, compatible with System V. | 278 | .El |
279 | .Pp | ||
280 | Unlike | ||
281 | .Tn GNU | ||
282 | .Fn getopt , | ||
283 | .Ox | ||
284 | does not permute the argument vector to allow non-options to be | ||
285 | interspersed with options on the command line. | ||
286 | Programs requiring this behavior should use | ||
287 | .Xr getopt_long 3 | ||
288 | instead. | ||
289 | Because of this (and unlike | ||
290 | .Tn GNU ) , | ||
291 | the | ||
292 | .Ox | ||
293 | .Fn getopt | ||
294 | supports optional arguments separated by whitespace. | ||
295 | .Sh HISTORY | ||
296 | The | ||
297 | .Fn getopt | ||
298 | function appeared in | ||
299 | .Bx 4.3 . | ||
300 | .Sh BUGS | ||
301 | The | ||
302 | .Fn getopt | ||
303 | function was once specified to return | ||
304 | .Dv EOF | ||
305 | instead of \-1. | ||
306 | This was changed by | ||
307 | .St -p1003.2-92 | ||
308 | to decouple | ||
309 | .Fn getopt | ||
310 | from | ||
311 | .Aq Pa stdio.h . | ||
233 | .Pp | 312 | .Pp |
234 | It is also possible to handle digits as option letters. | 313 | It is possible to handle digits as option letters. |
235 | This allows | 314 | This allows |
236 | .Fn getopt | 315 | .Fn getopt |
237 | to be used with programs that expect a number | 316 | to be used with programs that expect a number |
238 | .Pq Dq Li \&-\&3 | 317 | .Pq Dq Li \-3 |
239 | as an option. | 318 | as an option. |
240 | This practice is wrong, and should not be used in any current development. | 319 | This practice is wrong, and should not be used in any current development. |
241 | It is provided for backward compatibility | 320 | It is provided for backward compatibility |
242 | .Em only . | 321 | .Em only . |
243 | The following code fragment works in most cases. | 322 | The following code fragment works in most cases. |
244 | .Bd -literal -offset indent | 323 | .Bd -literal -offset indent |
245 | int length; | 324 | int ch; |
325 | long length; | ||
246 | char *p; | 326 | char *p; |
247 | 327 | ||
248 | while ((c = getopt(argc, argv, "0123456789")) != -1) | 328 | while ((ch = getopt(argc, argv, "0123456789")) != -1) { |
249 | switch (c) { | 329 | switch (ch) { |
250 | case '0': case '1': case '2': case '3': case '4': | 330 | case '0': case '1': case '2': case '3': case '4': |
251 | case '5': case '6': case '7': case '8': case '9': | 331 | case '5': case '6': case '7': case '8': case '9': |
252 | p = argv[optind - 1]; | 332 | p = argv[optind - 1]; |
253 | if (p[0] == '-' && p[1] == ch && !p[2]) | 333 | if (p[0] == '-' && p[1] == ch && !p[2]) |
254 | length = atoi(++p); | 334 | length = ch - '0'; |
255 | else | 335 | else |
256 | length = atoi(argv[optind] + 1); | 336 | length = strtol(argv[optind] + 1, NULL, 10); |
257 | break; | 337 | break; |
258 | } | 338 | } |
259 | } | 339 | } |