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37120919 AD |
1 | =head1 NAME |
2 | ||
3 | POSIX - Perl interface to IEEE Std 1003.1 | |
4 | ||
cb1a09d0 AD |
5 | =head1 SYNOPSIS |
6 | ||
7 | use POSIX; | |
8 | use POSIX qw(setsid); | |
9 | use POSIX qw(:errno_h :fcntl_h); | |
10 | ||
11 | printf "EINTR is %d\n", EINTR; | |
12 | ||
13 | $sess_id = POSIX::setsid(); | |
14 | ||
15 | $fd = POSIX::open($path, O_CREAT|O_EXCL|O_WRONLY, 0644); | |
16 | # note: that's a filedescriptor, *NOT* a filehandle | |
17 | ||
37120919 AD |
18 | =head1 DESCRIPTION |
19 | ||
20 | The POSIX module permits you to access all (or nearly all) the standard | |
21 | POSIX 1003.1 identifiers. Many of these identifiers have been given Perl-ish | |
90b1bb76 MS |
22 | interfaces. |
23 | ||
24 | I<Everything is exported by default> with the exception of any POSIX | |
25 | functions with the same name as a built-in Perl function, such as | |
26 | C<abs>, C<alarm>, C<rmdir>, C<write>, etc.., which will be exported | |
27 | only if you ask for them explicitly. This is an unfortunate backwards | |
e813f65e | 28 | compatibility feature. You can stop the exporting by saying C<use |
90b1bb76 | 29 | POSIX ()> and then use the fully qualified names (ie. C<POSIX::SEEK_END>). |
37120919 AD |
30 | |
31 | This document gives a condensed list of the features available in the POSIX | |
32 | module. Consult your operating system's manpages for general information on | |
33 | most features. Consult L<perlfunc> for functions which are noted as being | |
34 | identical to Perl's builtin functions. | |
35 | ||
36 | The first section describes POSIX functions from the 1003.1 specification. | |
37 | The second section describes some classes for signal objects, TTY objects, | |
38 | and other miscellaneous objects. The remaining sections list various | |
39 | constants and macros in an organization which roughly follows IEEE Std | |
40 | 1003.1b-1993. | |
41 | ||
37120919 AD |
42 | =head1 NOTE |
43 | ||
44 | The POSIX module is probably the most complex Perl module supplied with | |
45 | the standard distribution. It incorporates autoloading, namespace games, | |
46 | and dynamic loading of code that's in Perl, C, or both. It's a great | |
47 | source of wisdom. | |
48 | ||
49 | =head1 CAVEATS | |
50 | ||
51 | A few functions are not implemented because they are C specific. If you | |
52 | attempt to call these, they will print a message telling you that they | |
53 | aren't implemented, and suggest using the Perl equivalent should one | |
54 | exist. For example, trying to access the setjmp() call will elicit the | |
55 | message "setjmp() is C-specific: use eval {} instead". | |
56 | ||
57 | Furthermore, some evil vendors will claim 1003.1 compliance, but in fact | |
58 | are not so: they will not pass the PCTS (POSIX Compliance Test Suites). | |
59 | For example, one vendor may not define EDEADLK, or the semantics of the | |
60 | errno values set by open(2) might not be quite right. Perl does not | |
61 | attempt to verify POSIX compliance. That means you can currently | |
62 | successfully say "use POSIX", and then later in your program you find | |
63 | that your vendor has been lax and there's no usable ICANON macro after | |
64 | all. This could be construed to be a bug. | |
65 | ||
66 | =head1 FUNCTIONS | |
67 | ||
68 | =over 8 | |
69 | ||
70 | =item _exit | |
71 | ||
4755096e GS |
72 | This is identical to the C function C<_exit()>. It exits the program |
73 | immediately which means among other things buffered I/O is B<not> flushed. | |
37120919 | 74 | |
15978375 JH |
75 | Note that when using threads and in Linux this is B<not> a good way to |
76 | exit a thread because in Linux processes and threads are kind of the | |
77 | same thing (Note: while this is the situation in early 2003 there are | |
78 | projects under way to have threads with more POSIXly semantics in Linux). | |
79 | If you want not to return from a thread, detach the thread. | |
80 | ||
37120919 AD |
81 | =item abort |
82 | ||
4755096e GS |
83 | This is identical to the C function C<abort()>. It terminates the |
84 | process with a C<SIGABRT> signal unless caught by a signal handler or | |
85 | if the handler does not return normally (it e.g. does a C<longjmp>). | |
37120919 AD |
86 | |
87 | =item abs | |
88 | ||
4755096e GS |
89 | This is identical to Perl's builtin C<abs()> function, returning |
90 | the absolute value of its numerical argument. | |
37120919 AD |
91 | |
92 | =item access | |
93 | ||
94 | Determines the accessibility of a file. | |
95 | ||
96 | if( POSIX::access( "/", &POSIX::R_OK ) ){ | |
97 | print "have read permission\n"; | |
98 | } | |
99 | ||
4755096e GS |
100 | Returns C<undef> on failure. Note: do not use C<access()> for |
101 | security purposes. Between the C<access()> call and the operation | |
102 | you are preparing for the permissions might change: a classic | |
103 | I<race condition>. | |
37120919 AD |
104 | |
105 | =item acos | |
106 | ||
4755096e | 107 | This is identical to the C function C<acos()>, returning |
c2e66d9e | 108 | the arcus cosine of its numerical argument. See also L<Math::Trig>. |
37120919 AD |
109 | |
110 | =item alarm | |
111 | ||
4755096e GS |
112 | This is identical to Perl's builtin C<alarm()> function, |
113 | either for arming or disarming the C<SIGARLM> timer. | |
37120919 AD |
114 | |
115 | =item asctime | |
116 | ||
4755096e GS |
117 | This is identical to the C function C<asctime()>. It returns |
118 | a string of the form | |
119 | ||
120 | "Fri Jun 2 18:22:13 2000\n\0" | |
121 | ||
122 | and it is called thusly | |
123 | ||
124 | $asctime = asctime($sec, $min, $hour, $mday, $mon, $year, | |
125 | $wday, $yday, $isdst); | |
126 | ||
127 | The C<$mon> is zero-based: January equals C<0>. The C<$year> is | |
128 | 1900-based: 2001 equals C<101>. The C<$wday>, C<$yday>, and C<$isdst> | |
129 | default to zero (and the first two are usually ignored anyway). | |
37120919 AD |
130 | |
131 | =item asin | |
132 | ||
4755096e | 133 | This is identical to the C function C<asin()>, returning |
c2e66d9e | 134 | the arcus sine of its numerical argument. See also L<Math::Trig>. |
37120919 AD |
135 | |
136 | =item assert | |
137 | ||
4755096e GS |
138 | Unimplemented, but you can use L<perlfunc/die> and the L<Carp> module |
139 | to achieve similar things. | |
37120919 AD |
140 | |
141 | =item atan | |
142 | ||
4755096e | 143 | This is identical to the C function C<atan()>, returning the |
c2e66d9e | 144 | arcus tangent of its numerical argument. See also L<Math::Trig>. |
37120919 AD |
145 | |
146 | =item atan2 | |
147 | ||
4755096e GS |
148 | This is identical to Perl's builtin C<atan2()> function, returning |
149 | the arcus tangent defined by its two numerical arguments, the I<y> | |
c2e66d9e | 150 | coordinate and the I<x> coordinate. See also L<Math::Trig>. |
37120919 AD |
151 | |
152 | =item atexit | |
153 | ||
4755096e | 154 | atexit() is C-specific: use C<END {}> instead, see L<perlsub>. |
37120919 AD |
155 | |
156 | =item atof | |
157 | ||
4755096e GS |
158 | atof() is C-specific. Perl converts strings to numbers transparently. |
159 | If you need to force a scalar to a number, add a zero to it. | |
37120919 AD |
160 | |
161 | =item atoi | |
162 | ||
4755096e GS |
163 | atoi() is C-specific. Perl converts strings to numbers transparently. |
164 | If you need to force a scalar to a number, add a zero to it. | |
165 | If you need to have just the integer part, see L<perlfunc/int>. | |
37120919 AD |
166 | |
167 | =item atol | |
168 | ||
4755096e GS |
169 | atol() is C-specific. Perl converts strings to numbers transparently. |
170 | If you need to force a scalar to a number, add a zero to it. | |
171 | If you need to have just the integer part, see L<perlfunc/int>. | |
37120919 AD |
172 | |
173 | =item bsearch | |
174 | ||
4755096e GS |
175 | bsearch() not supplied. For doing binary search on wordlists, |
176 | see L<Search::Dict>. | |
37120919 AD |
177 | |
178 | =item calloc | |
179 | ||
4755096e | 180 | calloc() is C-specific. Perl does memory management transparently. |
37120919 AD |
181 | |
182 | =item ceil | |
183 | ||
4755096e GS |
184 | This is identical to the C function C<ceil()>, returning the smallest |
185 | integer value greater than or equal to the given numerical argument. | |
37120919 AD |
186 | |
187 | =item chdir | |
188 | ||
4755096e GS |
189 | This is identical to Perl's builtin C<chdir()> function, allowing |
190 | one to change the working (default) directory, see L<perlfunc/chdir>. | |
37120919 AD |
191 | |
192 | =item chmod | |
193 | ||
4755096e GS |
194 | This is identical to Perl's builtin C<chmod()> function, allowing |
195 | one to change file and directory permissions, see L<perlfunc/chmod>. | |
37120919 AD |
196 | |
197 | =item chown | |
198 | ||
4755096e GS |
199 | This is identical to Perl's builtin C<chown()> function, allowing one |
200 | to change file and directory owners and groups, see L<perlfunc/chown>. | |
37120919 AD |
201 | |
202 | =item clearerr | |
203 | ||
9d6eb86e | 204 | Use the method C<IO::Handle::clearerr()> instead, to reset the error |
4755096e | 205 | state (if any) and EOF state (if any) of the given stream. |
37120919 AD |
206 | |
207 | =item clock | |
208 | ||
4755096e GS |
209 | This is identical to the C function C<clock()>, returning the |
210 | amount of spent processor time in microseconds. | |
37120919 AD |
211 | |
212 | =item close | |
213 | ||
cb1a09d0 AD |
214 | Close the file. This uses file descriptors such as those obtained by calling |
215 | C<POSIX::open>. | |
216 | ||
217 | $fd = POSIX::open( "foo", &POSIX::O_RDONLY ); | |
218 | POSIX::close( $fd ); | |
37120919 AD |
219 | |
220 | Returns C<undef> on failure. | |
221 | ||
4755096e GS |
222 | See also L<perlfunc/close>. |
223 | ||
37120919 AD |
224 | =item closedir |
225 | ||
4755096e GS |
226 | This is identical to Perl's builtin C<closedir()> function for closing |
227 | a directory handle, see L<perlfunc/closedir>. | |
37120919 AD |
228 | |
229 | =item cos | |
230 | ||
4755096e GS |
231 | This is identical to Perl's builtin C<cos()> function, for returning |
232 | the cosine of its numerical argument, see L<perlfunc/cos>. | |
c2e66d9e | 233 | See also L<Math::Trig>. |
37120919 AD |
234 | |
235 | =item cosh | |
236 | ||
4755096e | 237 | This is identical to the C function C<cosh()>, for returning |
c2e66d9e | 238 | the hyperbolic cosine of its numeric argument. See also L<Math::Trig>. |
37120919 AD |
239 | |
240 | =item creat | |
241 | ||
cb1a09d0 AD |
242 | Create a new file. This returns a file descriptor like the ones returned by |
243 | C<POSIX::open>. Use C<POSIX::close> to close the file. | |
244 | ||
245 | $fd = POSIX::creat( "foo", 0611 ); | |
246 | POSIX::close( $fd ); | |
37120919 | 247 | |
4755096e GS |
248 | See also L<perlfunc/sysopen> and its C<O_CREAT> flag. |
249 | ||
37120919 AD |
250 | =item ctermid |
251 | ||
cb1a09d0 | 252 | Generates the path name for the controlling terminal. |
37120919 AD |
253 | |
254 | $path = POSIX::ctermid(); | |
255 | ||
256 | =item ctime | |
257 | ||
4755096e GS |
258 | This is identical to the C function C<ctime()> and equivalent |
259 | to C<asctime(localtime(...))>, see L</asctime> and L</localtime>. | |
37120919 AD |
260 | |
261 | =item cuserid | |
262 | ||
4755096e | 263 | Get the login name of the owner of the current process. |
37120919 AD |
264 | |
265 | $name = POSIX::cuserid(); | |
266 | ||
267 | =item difftime | |
268 | ||
4755096e GS |
269 | This is identical to the C function C<difftime()>, for returning |
270 | the time difference (in seconds) between two times (as returned | |
271 | by C<time()>), see L</time>. | |
37120919 AD |
272 | |
273 | =item div | |
274 | ||
4755096e GS |
275 | div() is C-specific, use L<perlfunc/int> on the usual C</> division and |
276 | the modulus C<%>. | |
37120919 AD |
277 | |
278 | =item dup | |
279 | ||
4755096e GS |
280 | This is similar to the C function C<dup()>, for duplicating a file |
281 | descriptor. | |
cb1a09d0 AD |
282 | |
283 | This uses file descriptors such as those obtained by calling | |
284 | C<POSIX::open>. | |
37120919 AD |
285 | |
286 | Returns C<undef> on failure. | |
287 | ||
288 | =item dup2 | |
289 | ||
4755096e GS |
290 | This is similar to the C function C<dup2()>, for duplicating a file |
291 | descriptor to an another known file descriptor. | |
cb1a09d0 AD |
292 | |
293 | This uses file descriptors such as those obtained by calling | |
294 | C<POSIX::open>. | |
37120919 AD |
295 | |
296 | Returns C<undef> on failure. | |
297 | ||
298 | =item errno | |
299 | ||
300 | Returns the value of errno. | |
301 | ||
302 | $errno = POSIX::errno(); | |
303 | ||
4755096e GS |
304 | This identical to the numerical values of the C<$!>, see L<perlvar/$ERRNO>. |
305 | ||
37120919 AD |
306 | =item execl |
307 | ||
4755096e | 308 | execl() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
309 | |
310 | =item execle | |
311 | ||
4755096e | 312 | execle() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
313 | |
314 | =item execlp | |
315 | ||
4755096e | 316 | execlp() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
317 | |
318 | =item execv | |
319 | ||
4755096e | 320 | execv() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
321 | |
322 | =item execve | |
323 | ||
4755096e | 324 | execve() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
325 | |
326 | =item execvp | |
327 | ||
4755096e | 328 | execvp() is C-specific, see L<perlfunc/exec>. |
37120919 AD |
329 | |
330 | =item exit | |
331 | ||
4755096e GS |
332 | This is identical to Perl's builtin C<exit()> function for exiting the |
333 | program, see L<perlfunc/exit>. | |
37120919 AD |
334 | |
335 | =item exp | |
336 | ||
4755096e GS |
337 | This is identical to Perl's builtin C<exp()> function for |
338 | returning the exponent (I<e>-based) of the numerical argument, | |
339 | see L<perlfunc/exp>. | |
37120919 AD |
340 | |
341 | =item fabs | |
342 | ||
4755096e GS |
343 | This is identical to Perl's builtin C<abs()> function for returning |
344 | the absolute value of the numerical argument, see L<perlfunc/abs>. | |
37120919 AD |
345 | |
346 | =item fclose | |
347 | ||
c2e66d9e | 348 | Use method C<IO::Handle::close()> instead, or see L<perlfunc/close>. |
37120919 AD |
349 | |
350 | =item fcntl | |
351 | ||
4755096e GS |
352 | This is identical to Perl's builtin C<fcntl()> function, |
353 | see L<perlfunc/fcntl>. | |
37120919 AD |
354 | |
355 | =item fdopen | |
356 | ||
c2e66d9e | 357 | Use method C<IO::Handle::new_from_fd()> instead, or see L<perlfunc/open>. |
37120919 AD |
358 | |
359 | =item feof | |
360 | ||
c2e66d9e | 361 | Use method C<IO::Handle::eof()> instead, or see L<perlfunc/eof>. |
37120919 AD |
362 | |
363 | =item ferror | |
364 | ||
28757baa | 365 | Use method C<IO::Handle::error()> instead. |
37120919 AD |
366 | |
367 | =item fflush | |
368 | ||
28757baa | 369 | Use method C<IO::Handle::flush()> instead. |
c2e66d9e | 370 | See also L<perlvar/$OUTPUT_AUTOFLUSH>. |
37120919 AD |
371 | |
372 | =item fgetc | |
373 | ||
c2e66d9e | 374 | Use method C<IO::Handle::getc()> instead, or see L<perlfunc/read>. |
37120919 AD |
375 | |
376 | =item fgetpos | |
377 | ||
c2e66d9e | 378 | Use method C<IO::Seekable::getpos()> instead, or see L<L/seek>. |
37120919 AD |
379 | |
380 | =item fgets | |
381 | ||
4755096e GS |
382 | Use method C<IO::Handle::gets()> instead. Similar to E<lt>E<gt>, also known |
383 | as L<perlfunc/readline>. | |
37120919 AD |
384 | |
385 | =item fileno | |
386 | ||
c2e66d9e | 387 | Use method C<IO::Handle::fileno()> instead, or see L<perlfunc/fileno>. |
37120919 AD |
388 | |
389 | =item floor | |
390 | ||
4755096e GS |
391 | This is identical to the C function C<floor()>, returning the largest |
392 | integer value less than or equal to the numerical argument. | |
37120919 AD |
393 | |
394 | =item fmod | |
395 | ||
396 | This is identical to the C function C<fmod()>. | |
397 | ||
847f7ebc | 398 | $r = fmod($x, $y); |
4755096e GS |
399 | |
400 | It returns the remainder C<$r = $x - $n*$y>, where C<$n = trunc($x/$y)>. | |
401 | The C<$r> has the same sign as C<$x> and magnitude (absolute value) | |
402 | less than the magnitude of C<$y>. | |
403 | ||
37120919 AD |
404 | =item fopen |
405 | ||
c2e66d9e | 406 | Use method C<IO::File::open()> instead, or see L<perlfunc/open>. |
37120919 AD |
407 | |
408 | =item fork | |
409 | ||
c2e66d9e GS |
410 | This is identical to Perl's builtin C<fork()> function |
411 | for duplicating the current process, see L<perlfunc/fork> | |
412 | and L<perlfork> if you are in Windows. | |
37120919 AD |
413 | |
414 | =item fpathconf | |
415 | ||
cb1a09d0 AD |
416 | Retrieves the value of a configurable limit on a file or directory. This |
417 | uses file descriptors such as those obtained by calling C<POSIX::open>. | |
418 | ||
419 | The following will determine the maximum length of the longest allowable | |
420 | pathname on the filesystem which holds C</tmp/foo>. | |
421 | ||
422 | $fd = POSIX::open( "/tmp/foo", &POSIX::O_RDONLY ); | |
423 | $path_max = POSIX::fpathconf( $fd, &POSIX::_PC_PATH_MAX ); | |
37120919 AD |
424 | |
425 | Returns C<undef> on failure. | |
426 | ||
427 | =item fprintf | |
428 | ||
4755096e | 429 | fprintf() is C-specific, see L<perlfunc/printf> instead. |
37120919 AD |
430 | |
431 | =item fputc | |
432 | ||
4755096e | 433 | fputc() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
434 | |
435 | =item fputs | |
436 | ||
4755096e | 437 | fputs() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
438 | |
439 | =item fread | |
440 | ||
4755096e | 441 | fread() is C-specific, see L<perlfunc/read> instead. |
37120919 AD |
442 | |
443 | =item free | |
444 | ||
4755096e | 445 | free() is C-specific. Perl does memory management transparently. |
37120919 AD |
446 | |
447 | =item freopen | |
448 | ||
4755096e | 449 | freopen() is C-specific, see L<perlfunc/open> instead. |
37120919 AD |
450 | |
451 | =item frexp | |
452 | ||
cb1a09d0 AD |
453 | Return the mantissa and exponent of a floating-point number. |
454 | ||
4755096e | 455 | ($mantissa, $exponent) = POSIX::frexp( 1.234e56 ); |
37120919 AD |
456 | |
457 | =item fscanf | |
458 | ||
4755096e | 459 | fscanf() is C-specific, use E<lt>E<gt> and regular expressions instead. |
37120919 AD |
460 | |
461 | =item fseek | |
462 | ||
c2e66d9e | 463 | Use method C<IO::Seekable::seek()> instead, or see L<perlfunc/seek>. |
37120919 AD |
464 | |
465 | =item fsetpos | |
466 | ||
c2e66d9e | 467 | Use method C<IO::Seekable::setpos()> instead, or seek L<perlfunc/seek>. |
37120919 AD |
468 | |
469 | =item fstat | |
470 | ||
cb1a09d0 AD |
471 | Get file status. This uses file descriptors such as those obtained by |
472 | calling C<POSIX::open>. The data returned is identical to the data from | |
473 | Perl's builtin C<stat> function. | |
474 | ||
475 | $fd = POSIX::open( "foo", &POSIX::O_RDONLY ); | |
476 | @stats = POSIX::fstat( $fd ); | |
37120919 | 477 | |
f0709b24 RGS |
478 | =item fsync |
479 | ||
480 | Use method C<IO::Handle::sync()> instead. | |
481 | ||
37120919 AD |
482 | =item ftell |
483 | ||
c2e66d9e | 484 | Use method C<IO::Seekable::tell()> instead, or see L<perlfunc/tell>. |
37120919 AD |
485 | |
486 | =item fwrite | |
487 | ||
4755096e | 488 | fwrite() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
489 | |
490 | =item getc | |
491 | ||
4755096e GS |
492 | This is identical to Perl's builtin C<getc()> function, |
493 | see L<perlfunc/getc>. | |
37120919 AD |
494 | |
495 | =item getchar | |
496 | ||
4755096e GS |
497 | Returns one character from STDIN. Identical to Perl's C<getc()>, |
498 | see L<perlfunc/getc>. | |
37120919 AD |
499 | |
500 | =item getcwd | |
501 | ||
502 | Returns the name of the current working directory. | |
4755096e | 503 | See also L<Cwd>. |
37120919 AD |
504 | |
505 | =item getegid | |
506 | ||
4755096e GS |
507 | Returns the effective group identifier. Similar to Perl' s builtin |
508 | variable C<$(>, see L<perlvar/$EGID>. | |
37120919 AD |
509 | |
510 | =item getenv | |
511 | ||
512 | Returns the value of the specified enironment variable. | |
4755096e | 513 | The same information is available through the C<%ENV> array. |
37120919 AD |
514 | |
515 | =item geteuid | |
516 | ||
4755096e GS |
517 | Returns the effective user identifier. Identical to Perl's builtin C<$E<gt>> |
518 | variable, see L<perlvar/$EUID>. | |
37120919 AD |
519 | |
520 | =item getgid | |
521 | ||
4755096e GS |
522 | Returns the user's real group identifier. Similar to Perl's builtin |
523 | variable C<$)>, see L<perlvar/$GID>. | |
37120919 AD |
524 | |
525 | =item getgrgid | |
526 | ||
4755096e GS |
527 | This is identical to Perl's builtin C<getgrgid()> function for |
528 | returning group entries by group identifiers, see | |
529 | L<perlfunc/getgrgid>. | |
37120919 AD |
530 | |
531 | =item getgrnam | |
532 | ||
4755096e GS |
533 | This is identical to Perl's builtin C<getgrnam()> function for |
534 | returning group entries by group names, see L<perlfunc/getgrnam>. | |
37120919 AD |
535 | |
536 | =item getgroups | |
537 | ||
4755096e GS |
538 | Returns the ids of the user's supplementary groups. Similar to Perl's |
539 | builtin variable C<$)>, see L<perlvar/$GID>. | |
37120919 AD |
540 | |
541 | =item getlogin | |
542 | ||
4755096e GS |
543 | This is identical to Perl's builtin C<getlogin()> function for |
544 | returning the user name associated with the current session, see | |
545 | L<perlfunc/getlogin>. | |
37120919 AD |
546 | |
547 | =item getpgrp | |
548 | ||
4755096e GS |
549 | This is identical to Perl's builtin C<getpgrp()> function for |
550 | returning the prcess group identifier of the current process, see | |
551 | L<perlfunc/getpgrp>. | |
37120919 AD |
552 | |
553 | =item getpid | |
554 | ||
4755096e GS |
555 | Returns the process identifier. Identical to Perl's builtin |
556 | variable C<$$>, see L<perlvar/$PID>. | |
37120919 AD |
557 | |
558 | =item getppid | |
559 | ||
4755096e GS |
560 | This is identical to Perl's builtin C<getppid()> function for |
561 | returning the process identifier of the parent process of the current | |
562 | process , see L<perlfunc/getppid>. | |
37120919 AD |
563 | |
564 | =item getpwnam | |
565 | ||
4755096e GS |
566 | This is identical to Perl's builtin C<getpwnam()> function for |
567 | returning user entries by user names, see L<perlfunc/getpwnam>. | |
37120919 AD |
568 | |
569 | =item getpwuid | |
570 | ||
4755096e GS |
571 | This is identical to Perl's builtin C<getpwuid()> function for |
572 | returning user entries by user identifiers, see L<perlfunc/getpwuid>. | |
37120919 AD |
573 | |
574 | =item gets | |
575 | ||
4755096e GS |
576 | Returns one line from C<STDIN>, similar to E<lt>E<gt>, also known |
577 | as the C<readline()> function, see L<perlfunc/readline>. | |
578 | ||
579 | B<NOTE>: if you have C programs that still use C<gets()>, be very | |
580 | afraid. The C<gets()> function is a source of endless grief because | |
581 | it has no buffer overrun checks. It should B<never> be used. The | |
582 | C<fgets()> function should be preferred instead. | |
37120919 AD |
583 | |
584 | =item getuid | |
585 | ||
4755096e GS |
586 | Returns the user's identifier. Identical to Perl's builtin C<$E<lt>> variable, |
587 | see L<perlvar/$UID>. | |
37120919 AD |
588 | |
589 | =item gmtime | |
590 | ||
4755096e GS |
591 | This is identical to Perl's builtin C<gmtime()> function for |
592 | converting seconds since the epoch to a date in Greenwich Mean Time, | |
593 | see L<perlfunc/gmtime>. | |
37120919 AD |
594 | |
595 | =item isalnum | |
596 | ||
f14c76ed RGS |
597 | This is identical to the C function, except that it can apply to a |
598 | single character or to a whole string. Note that locale settings may | |
599 | affect what characters are considered C<isalnum>. Does not work on | |
600 | Unicode characters code point 256 or higher. Consider using regular | |
601 | expressions and the C</[[:alnum:]]/> construct instead, or possibly | |
602 | the C</\w/> construct. | |
37120919 AD |
603 | |
604 | =item isalpha | |
605 | ||
f14c76ed RGS |
606 | This is identical to the C function, except that it can apply to |
607 | a single character or to a whole string. Note that locale settings | |
608 | may affect what characters are considered C<isalpha>. Does not work | |
609 | on Unicode characters code point 256 or higher. Consider using regular | |
610 | expressions and the C</[[:alpha:]]/> construct instead. | |
37120919 AD |
611 | |
612 | =item isatty | |
613 | ||
614 | Returns a boolean indicating whether the specified filehandle is connected | |
4755096e | 615 | to a tty. Similar to the C<-t> operator, see L<perlfunc/-X>. |
37120919 AD |
616 | |
617 | =item iscntrl | |
618 | ||
f14c76ed RGS |
619 | This is identical to the C function, except that it can apply to |
620 | a single character or to a whole string. Note that locale settings | |
621 | may affect what characters are considered C<iscntrl>. Does not work | |
622 | on Unicode characters code point 256 or higher. Consider using regular | |
623 | expressions and the C</[[:cntrl:]]/> construct instead. | |
37120919 AD |
624 | |
625 | =item isdigit | |
626 | ||
f14c76ed RGS |
627 | This is identical to the C function, except that it can apply to |
628 | a single character or to a whole string. Note that locale settings | |
629 | may affect what characters are considered C<isdigit> (unlikely, but | |
630 | still possible). Does not work on Unicode characters code point 256 | |
631 | or higher. Consider using regular expressions and the C</[[:digit:]]/> | |
632 | construct instead, or the C</\d/> construct. | |
37120919 AD |
633 | |
634 | =item isgraph | |
635 | ||
f14c76ed RGS |
636 | This is identical to the C function, except that it can apply to |
637 | a single character or to a whole string. Note that locale settings | |
638 | may affect what characters are considered C<isgraph>. Does not work | |
639 | on Unicode characters code point 256 or higher. Consider using regular | |
640 | expressions and the C</[[:graph:]]/> construct instead. | |
37120919 AD |
641 | |
642 | =item islower | |
643 | ||
f14c76ed RGS |
644 | This is identical to the C function, except that it can apply to |
645 | a single character or to a whole string. Note that locale settings | |
646 | may affect what characters are considered C<islower>. Does not work | |
647 | on Unicode characters code point 256 or higher. Consider using regular | |
648 | expressions and the C</[[:lower:]]/> construct instead. Do B<not> use | |
649 | C</[a-z]/>. | |
37120919 AD |
650 | |
651 | =item isprint | |
652 | ||
f14c76ed RGS |
653 | This is identical to the C function, except that it can apply to |
654 | a single character or to a whole string. Note that locale settings | |
655 | may affect what characters are considered C<isprint>. Does not work | |
656 | on Unicode characters code point 256 or higher. Consider using regular | |
657 | expressions and the C</[[:print:]]/> construct instead. | |
37120919 AD |
658 | |
659 | =item ispunct | |
660 | ||
f14c76ed RGS |
661 | This is identical to the C function, except that it can apply to |
662 | a single character or to a whole string. Note that locale settings | |
663 | may affect what characters are considered C<ispunct>. Does not work | |
664 | on Unicode characters code point 256 or higher. Consider using regular | |
665 | expressions and the C</[[:punct:]]/> construct instead. | |
37120919 AD |
666 | |
667 | =item isspace | |
668 | ||
f14c76ed RGS |
669 | This is identical to the C function, except that it can apply to |
670 | a single character or to a whole string. Note that locale settings | |
671 | may affect what characters are considered C<isspace>. Does not work | |
672 | on Unicode characters code point 256 or higher. Consider using regular | |
673 | expressions and the C</[[:space:]]/> construct instead, or the C</\s/> | |
674 | construct. (Note that C</\s/> and C</[[:space:]]/> are slightly | |
675 | different in that C</[[:space:]]/> can normally match a vertical tab, | |
676 | while C</\s/> does not.) | |
37120919 AD |
677 | |
678 | =item isupper | |
679 | ||
f14c76ed RGS |
680 | This is identical to the C function, except that it can apply to |
681 | a single character or to a whole string. Note that locale settings | |
682 | may affect what characters are considered C<isupper>. Does not work | |
683 | on Unicode characters code point 256 or higher. Consider using regular | |
684 | expressions and the C</[[:upper:]]/> construct instead. Do B<not> use | |
685 | C</[A-Z]/>. | |
37120919 AD |
686 | |
687 | =item isxdigit | |
688 | ||
cb1a09d0 | 689 | This is identical to the C function, except that it can apply to a single |
f14c76ed RGS |
690 | character or to a whole string. Note that locale settings may affect what |
691 | characters are considered C<isxdigit> (unlikely, but still possible). | |
692 | Does not work on Unicode characters code point 256 or higher. | |
693 | Consider using regular expressions and the C</[[:xdigit:]]/> | |
694 | construct instead, or simply C</[0-9a-f]/i>. | |
37120919 AD |
695 | |
696 | =item kill | |
697 | ||
4755096e | 698 | This is identical to Perl's builtin C<kill()> function for sending |
c2e66d9e | 699 | signals to processes (often to terminate them), see L<perlfunc/kill>. |
37120919 AD |
700 | |
701 | =item labs | |
702 | ||
4755096e GS |
703 | (For returning absolute values of long integers.) |
704 | labs() is C-specific, see L<perlfunc/abs> instead. | |
37120919 AD |
705 | |
706 | =item ldexp | |
707 | ||
4755096e GS |
708 | This is identical to the C function C<ldexp()> |
709 | for multiplying floating point numbers with powers of two. | |
710 | ||
711 | $x_quadrupled = POSIX::ldexp($x, 2); | |
37120919 AD |
712 | |
713 | =item ldiv | |
714 | ||
4755096e GS |
715 | (For computing dividends of long integers.) |
716 | ldiv() is C-specific, use C</> and C<int()> instead. | |
37120919 AD |
717 | |
718 | =item link | |
719 | ||
4755096e GS |
720 | This is identical to Perl's builtin C<link()> function |
721 | for creating hard links into files, see L<perlfunc/link>. | |
37120919 AD |
722 | |
723 | =item localeconv | |
724 | ||
cb1a09d0 AD |
725 | Get numeric formatting information. Returns a reference to a hash |
726 | containing the current locale formatting values. | |
727 | ||
4755096e | 728 | Here is how to query the database for the B<de> (Deutsch or German) locale. |
cb1a09d0 AD |
729 | |
730 | $loc = POSIX::setlocale( &POSIX::LC_ALL, "de" ); | |
731 | print "Locale = $loc\n"; | |
732 | $lconv = POSIX::localeconv(); | |
733 | print "decimal_point = ", $lconv->{decimal_point}, "\n"; | |
734 | print "thousands_sep = ", $lconv->{thousands_sep}, "\n"; | |
735 | print "grouping = ", $lconv->{grouping}, "\n"; | |
736 | print "int_curr_symbol = ", $lconv->{int_curr_symbol}, "\n"; | |
737 | print "currency_symbol = ", $lconv->{currency_symbol}, "\n"; | |
738 | print "mon_decimal_point = ", $lconv->{mon_decimal_point}, "\n"; | |
739 | print "mon_thousands_sep = ", $lconv->{mon_thousands_sep}, "\n"; | |
740 | print "mon_grouping = ", $lconv->{mon_grouping}, "\n"; | |
741 | print "positive_sign = ", $lconv->{positive_sign}, "\n"; | |
742 | print "negative_sign = ", $lconv->{negative_sign}, "\n"; | |
743 | print "int_frac_digits = ", $lconv->{int_frac_digits}, "\n"; | |
744 | print "frac_digits = ", $lconv->{frac_digits}, "\n"; | |
745 | print "p_cs_precedes = ", $lconv->{p_cs_precedes}, "\n"; | |
746 | print "p_sep_by_space = ", $lconv->{p_sep_by_space}, "\n"; | |
747 | print "n_cs_precedes = ", $lconv->{n_cs_precedes}, "\n"; | |
748 | print "n_sep_by_space = ", $lconv->{n_sep_by_space}, "\n"; | |
749 | print "p_sign_posn = ", $lconv->{p_sign_posn}, "\n"; | |
750 | print "n_sign_posn = ", $lconv->{n_sign_posn}, "\n"; | |
37120919 AD |
751 | |
752 | =item localtime | |
753 | ||
4755096e GS |
754 | This is identical to Perl's builtin C<localtime()> function for |
755 | converting seconds since the epoch to a date see L<perlfunc/localtime>. | |
37120919 AD |
756 | |
757 | =item log | |
758 | ||
4755096e GS |
759 | This is identical to Perl's builtin C<log()> function, |
760 | returning the natural (I<e>-based) logarithm of the numerical argument, | |
761 | see L<perlfunc/log>. | |
37120919 AD |
762 | |
763 | =item log10 | |
764 | ||
4755096e GS |
765 | This is identical to the C function C<log10()>, |
766 | returning the 10-base logarithm of the numerical argument. | |
767 | You can also use | |
768 | ||
769 | sub log10 { log($_[0]) / log(10) } | |
770 | ||
771 | or | |
772 | ||
773 | sub log10 { log($_[0]) / 2.30258509299405 } | |
774 | ||
775 | or | |
776 | ||
777 | sub log10 { log($_[0]) * 0.434294481903252 } | |
37120919 AD |
778 | |
779 | =item longjmp | |
780 | ||
4755096e | 781 | longjmp() is C-specific: use L<perlfunc/die> instead. |
37120919 AD |
782 | |
783 | =item lseek | |
784 | ||
8903cb82 | 785 | Move the file's read/write position. This uses file descriptors such as |
cb1a09d0 AD |
786 | those obtained by calling C<POSIX::open>. |
787 | ||
788 | $fd = POSIX::open( "foo", &POSIX::O_RDONLY ); | |
789 | $off_t = POSIX::lseek( $fd, 0, &POSIX::SEEK_SET ); | |
37120919 AD |
790 | |
791 | Returns C<undef> on failure. | |
792 | ||
793 | =item malloc | |
794 | ||
4755096e | 795 | malloc() is C-specific. Perl does memory management transparently. |
37120919 AD |
796 | |
797 | =item mblen | |
798 | ||
cb1a09d0 | 799 | This is identical to the C function C<mblen()>. |
4755096e GS |
800 | Perl does not have any support for the wide and multibyte |
801 | characters of the C standards, so this might be a rather | |
802 | useless function. | |
37120919 AD |
803 | |
804 | =item mbstowcs | |
805 | ||
cb1a09d0 | 806 | This is identical to the C function C<mbstowcs()>. |
4755096e GS |
807 | Perl does not have any support for the wide and multibyte |
808 | characters of the C standards, so this might be a rather | |
809 | useless function. | |
37120919 AD |
810 | |
811 | =item mbtowc | |
812 | ||
cb1a09d0 | 813 | This is identical to the C function C<mbtowc()>. |
4755096e GS |
814 | Perl does not have any support for the wide and multibyte |
815 | characters of the C standards, so this might be a rather | |
816 | useless function. | |
37120919 AD |
817 | |
818 | =item memchr | |
819 | ||
4755096e | 820 | memchr() is C-specific, see L<perlfunc/index> instead. |
37120919 AD |
821 | |
822 | =item memcmp | |
823 | ||
4755096e | 824 | memcmp() is C-specific, use C<eq> instead, see L<perlop>. |
37120919 AD |
825 | |
826 | =item memcpy | |
827 | ||
4755096e | 828 | memcpy() is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>. |
37120919 AD |
829 | |
830 | =item memmove | |
831 | ||
4755096e | 832 | memmove() is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>. |
37120919 AD |
833 | |
834 | =item memset | |
835 | ||
4755096e | 836 | memset() is C-specific, use C<x> instead, see L<perlop>. |
37120919 AD |
837 | |
838 | =item mkdir | |
839 | ||
4755096e GS |
840 | This is identical to Perl's builtin C<mkdir()> function |
841 | for creating directories, see L<perlfunc/mkdir>. | |
37120919 AD |
842 | |
843 | =item mkfifo | |
844 | ||
4755096e GS |
845 | This is similar to the C function C<mkfifo()> for creating |
846 | FIFO special files. | |
37120919 | 847 | |
4755096e GS |
848 | if (mkfifo($path, $mode)) { .... |
849 | ||
850 | Returns C<undef> on failure. The C<$mode> is similar to the | |
851 | mode of C<mkdir()>, see L<perlfunc/mkdir>. | |
37120919 AD |
852 | |
853 | =item mktime | |
854 | ||
cb1a09d0 AD |
855 | Convert date/time info to a calendar time. |
856 | ||
857 | Synopsis: | |
858 | ||
859 | mktime(sec, min, hour, mday, mon, year, wday = 0, yday = 0, isdst = 0) | |
860 | ||
861 | The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero. | |
862 | I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The | |
863 | year (C<year>) is given in years since 1900. I.e. The year 1995 is 95; the | |
864 | year 2001 is 101. Consult your system's C<mktime()> manpage for details | |
865 | about these and the other arguments. | |
866 | ||
867 | Calendar time for December 12, 1995, at 10:30 am. | |
868 | ||
869 | $time_t = POSIX::mktime( 0, 30, 10, 12, 11, 95 ); | |
870 | print "Date = ", POSIX::ctime($time_t); | |
37120919 AD |
871 | |
872 | Returns C<undef> on failure. | |
873 | ||
874 | =item modf | |
875 | ||
cb1a09d0 AD |
876 | Return the integral and fractional parts of a floating-point number. |
877 | ||
878 | ($fractional, $integral) = POSIX::modf( 3.14 ); | |
37120919 AD |
879 | |
880 | =item nice | |
881 | ||
4755096e GS |
882 | This is similar to the C function C<nice()>, for changing |
883 | the scheduling preference of the current process. Positive | |
884 | arguments mean more polite process, negative values more | |
885 | needy process. Normal user processes can only be more polite. | |
37120919 AD |
886 | |
887 | Returns C<undef> on failure. | |
888 | ||
889 | =item offsetof | |
890 | ||
4755096e | 891 | offsetof() is C-specific, you probably want to see L<perlfunc/pack> instead. |
37120919 AD |
892 | |
893 | =item open | |
894 | ||
cb1a09d0 AD |
895 | Open a file for reading for writing. This returns file descriptors, not |
896 | Perl filehandles. Use C<POSIX::close> to close the file. | |
897 | ||
898 | Open a file read-only with mode 0666. | |
899 | ||
900 | $fd = POSIX::open( "foo" ); | |
901 | ||
902 | Open a file for read and write. | |
903 | ||
904 | $fd = POSIX::open( "foo", &POSIX::O_RDWR ); | |
905 | ||
906 | Open a file for write, with truncation. | |
907 | ||
908 | $fd = POSIX::open( "foo", &POSIX::O_WRONLY | &POSIX::O_TRUNC ); | |
909 | ||
910 | Create a new file with mode 0640. Set up the file for writing. | |
911 | ||
912 | $fd = POSIX::open( "foo", &POSIX::O_CREAT | &POSIX::O_WRONLY, 0640 ); | |
37120919 AD |
913 | |
914 | Returns C<undef> on failure. | |
915 | ||
4755096e GS |
916 | See also L<perlfunc/sysopen>. |
917 | ||
37120919 AD |
918 | =item opendir |
919 | ||
cb1a09d0 AD |
920 | Open a directory for reading. |
921 | ||
922 | $dir = POSIX::opendir( "/tmp" ); | |
923 | @files = POSIX::readdir( $dir ); | |
924 | POSIX::closedir( $dir ); | |
925 | ||
926 | Returns C<undef> on failure. | |
37120919 AD |
927 | |
928 | =item pathconf | |
929 | ||
930 | Retrieves the value of a configurable limit on a file or directory. | |
931 | ||
932 | The following will determine the maximum length of the longest allowable | |
933 | pathname on the filesystem which holds C</tmp>. | |
934 | ||
935 | $path_max = POSIX::pathconf( "/tmp", &POSIX::_PC_PATH_MAX ); | |
936 | ||
937 | Returns C<undef> on failure. | |
938 | ||
939 | =item pause | |
940 | ||
4755096e GS |
941 | This is similar to the C function C<pause()>, which suspends |
942 | the execution of the current process until a signal is received. | |
37120919 AD |
943 | |
944 | Returns C<undef> on failure. | |
945 | ||
946 | =item perror | |
947 | ||
4755096e GS |
948 | This is identical to the C function C<perror()>, which outputs to the |
949 | standard error stream the specified message followed by ": " and the | |
950 | current error string. Use the C<warn()> function and the C<$!> | |
951 | variable instead, see L<perlfunc/warn> and L<perlvar/$ERRNO>. | |
37120919 AD |
952 | |
953 | =item pipe | |
954 | ||
cb1a09d0 AD |
955 | Create an interprocess channel. This returns file descriptors like those |
956 | returned by C<POSIX::open>. | |
957 | ||
958 | ($fd0, $fd1) = POSIX::pipe(); | |
959 | POSIX::write( $fd0, "hello", 5 ); | |
960 | POSIX::read( $fd1, $buf, 5 ); | |
37120919 | 961 | |
4755096e GS |
962 | See also L<perlfunc/pipe>. |
963 | ||
37120919 AD |
964 | =item pow |
965 | ||
4755096e | 966 | Computes C<$x> raised to the power C<$exponent>. |
37120919 AD |
967 | |
968 | $ret = POSIX::pow( $x, $exponent ); | |
969 | ||
4755096e GS |
970 | You can also use the C<**> operator, see L<perlop>. |
971 | ||
37120919 AD |
972 | =item printf |
973 | ||
4755096e GS |
974 | Formats and prints the specified arguments to STDOUT. |
975 | See also L<perlfunc/printf>. | |
37120919 AD |
976 | |
977 | =item putc | |
978 | ||
4755096e | 979 | putc() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
980 | |
981 | =item putchar | |
982 | ||
4755096e | 983 | putchar() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
984 | |
985 | =item puts | |
986 | ||
4755096e | 987 | puts() is C-specific, see L<perlfunc/print> instead. |
37120919 AD |
988 | |
989 | =item qsort | |
990 | ||
4755096e | 991 | qsort() is C-specific, see L<perlfunc/sort> instead. |
37120919 AD |
992 | |
993 | =item raise | |
994 | ||
995 | Sends the specified signal to the current process. | |
4755096e | 996 | See also L<perlfunc/kill> and the C<$$> in L<perlvar/$PID>. |
37120919 AD |
997 | |
998 | =item rand | |
999 | ||
4755096e | 1000 | C<rand()> is non-portable, see L<perlfunc/rand> instead. |
37120919 AD |
1001 | |
1002 | =item read | |
1003 | ||
cb1a09d0 AD |
1004 | Read from a file. This uses file descriptors such as those obtained by |
1005 | calling C<POSIX::open>. If the buffer C<$buf> is not large enough for the | |
1006 | read then Perl will extend it to make room for the request. | |
1007 | ||
1008 | $fd = POSIX::open( "foo", &POSIX::O_RDONLY ); | |
1009 | $bytes = POSIX::read( $fd, $buf, 3 ); | |
37120919 AD |
1010 | |
1011 | Returns C<undef> on failure. | |
1012 | ||
4755096e GS |
1013 | See also L<perlfunc/sysread>. |
1014 | ||
37120919 AD |
1015 | =item readdir |
1016 | ||
4755096e GS |
1017 | This is identical to Perl's builtin C<readdir()> function |
1018 | for reading directory entries, see L<perlfunc/readdir>. | |
37120919 AD |
1019 | |
1020 | =item realloc | |
1021 | ||
4755096e | 1022 | realloc() is C-specific. Perl does memory management transparently. |
37120919 AD |
1023 | |
1024 | =item remove | |
1025 | ||
4755096e GS |
1026 | This is identical to Perl's builtin C<unlink()> function |
1027 | for removing files, see L<perlfunc/unlink>. | |
37120919 AD |
1028 | |
1029 | =item rename | |
1030 | ||
4755096e GS |
1031 | This is identical to Perl's builtin C<rename()> function |
1032 | for renaming files, see L<perlfunc/rename>. | |
37120919 AD |
1033 | |
1034 | =item rewind | |
1035 | ||
1036 | Seeks to the beginning of the file. | |
1037 | ||
1038 | =item rewinddir | |
1039 | ||
4755096e GS |
1040 | This is identical to Perl's builtin C<rewinddir()> function for |
1041 | rewinding directory entry streams, see L<perlfunc/rewinddir>. | |
37120919 AD |
1042 | |
1043 | =item rmdir | |
1044 | ||
4755096e GS |
1045 | This is identical to Perl's builtin C<rmdir()> function |
1046 | for removing (empty) directories, see L<perlfunc/rmdir>. | |
37120919 AD |
1047 | |
1048 | =item scanf | |
1049 | ||
4755096e GS |
1050 | scanf() is C-specific, use E<lt>E<gt> and regular expressions instead, |
1051 | see L<perlre>. | |
37120919 AD |
1052 | |
1053 | =item setgid | |
1054 | ||
a043a685 GW |
1055 | Sets the real group identifier and the effective group identifier for |
1056 | this process. Similar to assigning a value to the Perl's builtin | |
1057 | C<$)> variable, see L<perlvar/$GID>, except that the latter | |
1058 | will change only the real user identifier, and that the setgid() | |
1059 | uses only a single numeric argument, as opposed to a space-separated | |
1060 | list of numbers. | |
37120919 AD |
1061 | |
1062 | =item setjmp | |
1063 | ||
4755096e GS |
1064 | C<setjmp()> is C-specific: use C<eval {}> instead, |
1065 | see L<perlfunc/eval>. | |
37120919 AD |
1066 | |
1067 | =item setlocale | |
1068 | ||
c26abfa6 JH |
1069 | Modifies and queries program's locale. The following examples assume |
1070 | ||
1071 | use POSIX qw(setlocale LC_ALL LC_CTYPE); | |
1072 | ||
1073 | has been issued. | |
37120919 | 1074 | |
8966fa01 JH |
1075 | The following will set the traditional UNIX system locale behavior |
1076 | (the second argument C<"C">). | |
37120919 | 1077 | |
c26abfa6 | 1078 | $loc = setlocale( LC_ALL, "C" ); |
37120919 | 1079 | |
c26abfa6 JH |
1080 | The following will query the current LC_CTYPE category. (No second |
1081 | argument means 'query'.) | |
8966fa01 | 1082 | |
c26abfa6 | 1083 | $loc = setlocale( LC_CTYPE ); |
8966fa01 JH |
1084 | |
1085 | The following will set the LC_CTYPE behaviour according to the locale | |
1086 | environment variables (the second argument C<"">). | |
9d6eb86e | 1087 | Please see your systems C<setlocale(3)> documentation for the locale |
71be2cbc | 1088 | environment variables' meaning or consult L<perllocale>. |
8966fa01 | 1089 | |
c26abfa6 | 1090 | $loc = setlocale( LC_CTYPE, "" ); |
8966fa01 JH |
1091 | |
1092 | The following will set the LC_COLLATE behaviour to Argentinian | |
1093 | Spanish. B<NOTE>: The naming and availability of locales depends on | |
71be2cbc | 1094 | your operating system. Please consult L<perllocale> for how to find |
8966fa01 JH |
1095 | out which locales are available in your system. |
1096 | ||
c26abfa6 | 1097 | $loc = setlocale( LC_ALL, "es_AR.ISO8859-1" ); |
8966fa01 | 1098 | |
37120919 AD |
1099 | =item setpgid |
1100 | ||
4755096e GS |
1101 | This is similar to the C function C<setpgid()> for |
1102 | setting the process group identifier of the current process. | |
37120919 AD |
1103 | |
1104 | Returns C<undef> on failure. | |
1105 | ||
1106 | =item setsid | |
1107 | ||
4755096e GS |
1108 | This is identical to the C function C<setsid()> for |
1109 | setting the session identifier of the current process. | |
37120919 AD |
1110 | |
1111 | =item setuid | |
1112 | ||
a043a685 GW |
1113 | Sets the real user identifier and the effective user identifier for |
1114 | this process. Similar to assigning a value to the Perl's builtin | |
1115 | C<$E<lt>> variable, see L<perlvar/$UID>, except that the latter | |
1116 | will change only the real user identifier. | |
37120919 AD |
1117 | |
1118 | =item sigaction | |
1119 | ||
cb1a09d0 AD |
1120 | Detailed signal management. This uses C<POSIX::SigAction> objects for the |
1121 | C<action> and C<oldaction> arguments. Consult your system's C<sigaction> | |
1122 | manpage for details. | |
1123 | ||
1124 | Synopsis: | |
1125 | ||
1126 | sigaction(sig, action, oldaction = 0) | |
37120919 AD |
1127 | |
1128 | Returns C<undef> on failure. | |
1129 | ||
1130 | =item siglongjmp | |
1131 | ||
4755096e | 1132 | siglongjmp() is C-specific: use L<perlfunc/die> instead. |
37120919 AD |
1133 | |
1134 | =item sigpending | |
1135 | ||
cb1a09d0 AD |
1136 | Examine signals that are blocked and pending. This uses C<POSIX::SigSet> |
1137 | objects for the C<sigset> argument. Consult your system's C<sigpending> | |
1138 | manpage for details. | |
1139 | ||
1140 | Synopsis: | |
1141 | ||
1142 | sigpending(sigset) | |
37120919 AD |
1143 | |
1144 | Returns C<undef> on failure. | |
1145 | ||
1146 | =item sigprocmask | |
1147 | ||
cb1a09d0 AD |
1148 | Change and/or examine calling process's signal mask. This uses |
1149 | C<POSIX::SigSet> objects for the C<sigset> and C<oldsigset> arguments. | |
1150 | Consult your system's C<sigprocmask> manpage for details. | |
1151 | ||
1152 | Synopsis: | |
1153 | ||
1154 | sigprocmask(how, sigset, oldsigset = 0) | |
37120919 AD |
1155 | |
1156 | Returns C<undef> on failure. | |
1157 | ||
1158 | =item sigsetjmp | |
1159 | ||
4755096e GS |
1160 | C<sigsetjmp()> is C-specific: use C<eval {}> instead, |
1161 | see L<perlfunc/eval>. | |
37120919 AD |
1162 | |
1163 | =item sigsuspend | |
1164 | ||
cb1a09d0 AD |
1165 | Install a signal mask and suspend process until signal arrives. This uses |
1166 | C<POSIX::SigSet> objects for the C<signal_mask> argument. Consult your | |
1167 | system's C<sigsuspend> manpage for details. | |
1168 | ||
1169 | Synopsis: | |
1170 | ||
1171 | sigsuspend(signal_mask) | |
37120919 AD |
1172 | |
1173 | Returns C<undef> on failure. | |
1174 | ||
1175 | =item sin | |
1176 | ||
4755096e GS |
1177 | This is identical to Perl's builtin C<sin()> function |
1178 | for returning the sine of the numerical argument, | |
c2e66d9e | 1179 | see L<perlfunc/sin>. See also L<Math::Trig>. |
37120919 AD |
1180 | |
1181 | =item sinh | |
1182 | ||
4755096e GS |
1183 | This is identical to the C function C<sinh()> |
1184 | for returning the hyperbolic sine of the numerical argument. | |
c2e66d9e | 1185 | See also L<Math::Trig>. |
37120919 AD |
1186 | |
1187 | =item sleep | |
1188 | ||
2ab27a20 A |
1189 | This is functionally identical to Perl's builtin C<sleep()> function |
1190 | for suspending the execution of the current for process for certain | |
1191 | number of seconds, see L<perlfunc/sleep>. There is one signifanct | |
2bad225e | 1192 | difference, however: C<POSIX::sleep()> returns the number of |
2ab27a20 A |
1193 | B<unslept> seconds, while the C<CORE::sleep()> returns the |
1194 | number of slept seconds. | |
37120919 AD |
1195 | |
1196 | =item sprintf | |
1197 | ||
4755096e GS |
1198 | This is similar to Perl's builtin C<sprintf()> function |
1199 | for returning a string that has the arguments formatted as requested, | |
1200 | see L<perlfunc/sprintf>. | |
37120919 AD |
1201 | |
1202 | =item sqrt | |
1203 | ||
1204 | This is identical to Perl's builtin C<sqrt()> function. | |
4755096e GS |
1205 | for returning the square root of the numerical argument, |
1206 | see L<perlfunc/sqrt>. | |
37120919 AD |
1207 | |
1208 | =item srand | |
1209 | ||
4755096e | 1210 | Give a seed the pseudorandom number generator, see L<perlfunc/srand>. |
37120919 AD |
1211 | |
1212 | =item sscanf | |
1213 | ||
4755096e GS |
1214 | sscanf() is C-specific, use regular expressions instead, |
1215 | see L<perlre>. | |
37120919 AD |
1216 | |
1217 | =item stat | |
1218 | ||
4755096e GS |
1219 | This is identical to Perl's builtin C<stat()> function |
1220 | for retutning information about files and directories. | |
37120919 AD |
1221 | |
1222 | =item strcat | |
1223 | ||
4755096e | 1224 | strcat() is C-specific, use C<.=> instead, see L<perlop>. |
37120919 AD |
1225 | |
1226 | =item strchr | |
1227 | ||
4755096e | 1228 | strchr() is C-specific, see L<perlfunc/index> instead. |
37120919 AD |
1229 | |
1230 | =item strcmp | |
1231 | ||
4755096e | 1232 | strcmp() is C-specific, use C<eq> or C<cmp> instead, see L<perlop>. |
37120919 AD |
1233 | |
1234 | =item strcoll | |
1235 | ||
4755096e GS |
1236 | This is identical to the C function C<strcoll()> |
1237 | for collating (comparing) strings transformed using | |
1238 | the C<strxfrm()> function. Not really needed since | |
1239 | Perl can do this transparently, see L<perllocale>. | |
37120919 AD |
1240 | |
1241 | =item strcpy | |
1242 | ||
4755096e | 1243 | strcpy() is C-specific, use C<=> instead, see L<perlop>. |
37120919 AD |
1244 | |
1245 | =item strcspn | |
1246 | ||
4755096e GS |
1247 | strcspn() is C-specific, use regular expressions instead, |
1248 | see L<perlre>. | |
37120919 AD |
1249 | |
1250 | =item strerror | |
1251 | ||
1252 | Returns the error string for the specified errno. | |
4755096e | 1253 | Identical to the string form of the C<$!>, see L<perlvar/$ERRNO>. |
37120919 AD |
1254 | |
1255 | =item strftime | |
1256 | ||
cb1a09d0 AD |
1257 | Convert date and time information to string. Returns the string. |
1258 | ||
1259 | Synopsis: | |
1260 | ||
e44f695e | 1261 | strftime(fmt, sec, min, hour, mday, mon, year, wday = -1, yday = -1, isdst = -1) |
cb1a09d0 AD |
1262 | |
1263 | The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero. | |
1264 | I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The | |
e44f695e | 1265 | year (C<year>) is given in years since 1900. I.e., the year 1995 is 95; the |
cb1a09d0 | 1266 | year 2001 is 101. Consult your system's C<strftime()> manpage for details |
659b4938 | 1267 | about these and the other arguments. |
f14c76ed | 1268 | |
659b4938 DD |
1269 | If you want your code to be portable, your format (C<fmt>) argument |
1270 | should use only the conversion specifiers defined by the ANSI C | |
f14c76ed RGS |
1271 | standard (C89, to play safe). These are C<aAbBcdHIjmMpSUwWxXyYZ%>. |
1272 | But even then, the B<results> of some of the conversion specifiers are | |
1273 | non-portable. For example, the specifiers C<aAbBcpZ> change according | |
1274 | to the locale settings of the user, and both how to set locales (the | |
1275 | locale names) and what output to expect are non-standard. | |
1276 | The specifier C<c> changes according to the timezone settings of the | |
1277 | user and the timezone computation rules of the operating system. | |
1278 | The C<Z> specifier is notoriously unportable since the names of | |
1279 | timezones are non-standard. Sticking to the numeric specifiers is the | |
1280 | safest route. | |
1281 | ||
1282 | The given arguments are made consistent as though by calling | |
1283 | C<mktime()> before calling your system's C<strftime()> function, | |
1284 | except that the C<isdst> value is not affected. | |
cb1a09d0 AD |
1285 | |
1286 | The string for Tuesday, December 12, 1995. | |
1287 | ||
1288 | $str = POSIX::strftime( "%A, %B %d, %Y", 0, 0, 0, 12, 11, 95, 2 ); | |
1289 | print "$str\n"; | |
37120919 AD |
1290 | |
1291 | =item strlen | |
1292 | ||
4755096e | 1293 | strlen() is C-specific, use C<length()> instead, see L<perlfunc/length>. |
37120919 AD |
1294 | |
1295 | =item strncat | |
1296 | ||
4755096e | 1297 | strncat() is C-specific, use C<.=> instead, see L<perlop>. |
37120919 AD |
1298 | |
1299 | =item strncmp | |
1300 | ||
4755096e | 1301 | strncmp() is C-specific, use C<eq> instead, see L<perlop>. |
37120919 AD |
1302 | |
1303 | =item strncpy | |
1304 | ||
4755096e | 1305 | strncpy() is C-specific, use C<=> instead, see L<perlop>. |
37120919 AD |
1306 | |
1307 | =item strpbrk | |
1308 | ||
4755096e GS |
1309 | strpbrk() is C-specific, use regular expressions instead, |
1310 | see L<perlre>. | |
37120919 AD |
1311 | |
1312 | =item strrchr | |
1313 | ||
4755096e | 1314 | strrchr() is C-specific, see L<perlfunc/rindex> instead. |
37120919 AD |
1315 | |
1316 | =item strspn | |
1317 | ||
4755096e GS |
1318 | strspn() is C-specific, use regular expressions instead, |
1319 | see L<perlre>. | |
37120919 AD |
1320 | |
1321 | =item strstr | |
1322 | ||
4755096e GS |
1323 | This is identical to Perl's builtin C<index()> function, |
1324 | see L<perlfunc/index>. | |
37120919 AD |
1325 | |
1326 | =item strtod | |
1327 | ||
a89d8a78 DH |
1328 | String to double translation. Returns the parsed number and the number |
1329 | of characters in the unparsed portion of the string. Truly | |
1330 | POSIX-compliant systems set $! ($ERRNO) to indicate a translation | |
1331 | error, so clear $! before calling strtod. However, non-POSIX systems | |
1332 | may not check for overflow, and therefore will never set $!. | |
1333 | ||
1334 | strtod should respect any POSIX I<setlocale()> settings. | |
1335 | ||
1336 | To parse a string $str as a floating point number use | |
1337 | ||
1338 | $! = 0; | |
1339 | ($num, $n_unparsed) = POSIX::strtod($str); | |
1340 | ||
1341 | The second returned item and $! can be used to check for valid input: | |
1342 | ||
1343 | if (($str eq '') || ($n_unparsed != 0) || !$!) { | |
1344 | die "Non-numeric input $str" . $! ? ": $!\n" : "\n"; | |
1345 | } | |
1346 | ||
1347 | When called in a scalar context strtod returns the parsed number. | |
37120919 AD |
1348 | |
1349 | =item strtok | |
1350 | ||
4755096e GS |
1351 | strtok() is C-specific, use regular expressions instead, see |
1352 | L<perlre>, or L<perlfunc/split>. | |
37120919 AD |
1353 | |
1354 | =item strtol | |
1355 | ||
a89d8a78 DH |
1356 | String to (long) integer translation. Returns the parsed number and |
1357 | the number of characters in the unparsed portion of the string. Truly | |
1358 | POSIX-compliant systems set $! ($ERRNO) to indicate a translation | |
1359 | error, so clear $! before calling strtol. However, non-POSIX systems | |
1360 | may not check for overflow, and therefore will never set $!. | |
1361 | ||
1362 | strtol should respect any POSIX I<setlocale()> settings. | |
1363 | ||
1364 | To parse a string $str as a number in some base $base use | |
1365 | ||
1366 | $! = 0; | |
1367 | ($num, $n_unparsed) = POSIX::strtol($str, $base); | |
1368 | ||
1369 | The base should be zero or between 2 and 36, inclusive. When the base | |
1370 | is zero or omitted strtol will use the string itself to determine the | |
1371 | base: a leading "0x" or "0X" means hexadecimal; a leading "0" means | |
1372 | octal; any other leading characters mean decimal. Thus, "1234" is | |
1373 | parsed as a decimal number, "01234" as an octal number, and "0x1234" | |
1374 | as a hexadecimal number. | |
1375 | ||
1376 | The second returned item and $! can be used to check for valid input: | |
1377 | ||
1378 | if (($str eq '') || ($n_unparsed != 0) || !$!) { | |
1379 | die "Non-numeric input $str" . $! ? ": $!\n" : "\n"; | |
1380 | } | |
1381 | ||
1382 | When called in a scalar context strtol returns the parsed number. | |
1383 | ||
1384 | =item strtoul | |
1385 | ||
4755096e GS |
1386 | String to unsigned (long) integer translation. strtoul() is identical |
1387 | to strtol() except that strtoul() only parses unsigned integers. See | |
1388 | L</strtol> for details. | |
a89d8a78 | 1389 | |
4755096e GS |
1390 | Note: Some vendors supply strtod() and strtol() but not strtoul(). |
1391 | Other vendors that do supply strtoul() parse "-1" as a valid value. | |
37120919 AD |
1392 | |
1393 | =item strxfrm | |
1394 | ||
cb1a09d0 AD |
1395 | String transformation. Returns the transformed string. |
1396 | ||
1397 | $dst = POSIX::strxfrm( $src ); | |
37120919 | 1398 | |
4755096e GS |
1399 | Used in conjunction with the C<strcoll()> function, see L</strcoll>. |
1400 | ||
1401 | Not really needed since Perl can do this transparently, see | |
1402 | L<perllocale>. | |
1403 | ||
37120919 AD |
1404 | =item sysconf |
1405 | ||
1406 | Retrieves values of system configurable variables. | |
1407 | ||
1408 | The following will get the machine's clock speed. | |
1409 | ||
1410 | $clock_ticks = POSIX::sysconf( &POSIX::_SC_CLK_TCK ); | |
1411 | ||
1412 | Returns C<undef> on failure. | |
1413 | ||
1414 | =item system | |
1415 | ||
4755096e GS |
1416 | This is identical to Perl's builtin C<system()> function, see |
1417 | L<perlfunc/system>. | |
37120919 AD |
1418 | |
1419 | =item tan | |
1420 | ||
4755096e | 1421 | This is identical to the C function C<tan()>, returning the |
c2e66d9e | 1422 | tangent of the numerical argument. See also L<Math::Trig>. |
37120919 AD |
1423 | |
1424 | =item tanh | |
1425 | ||
4755096e | 1426 | This is identical to the C function C<tanh()>, returning the |
c2e66d9e | 1427 | hyperbolic tangent of the numerical argument. See also L<Math::Trig>. |
37120919 AD |
1428 | |
1429 | =item tcdrain | |
1430 | ||
4755096e GS |
1431 | This is similar to the C function C<tcdrain()> for draining |
1432 | the output queue of its argument stream. | |
37120919 AD |
1433 | |
1434 | Returns C<undef> on failure. | |
1435 | ||
1436 | =item tcflow | |
1437 | ||
4755096e GS |
1438 | This is similar to the C function C<tcflow()> for controlling |
1439 | the flow of its argument stream. | |
37120919 AD |
1440 | |
1441 | Returns C<undef> on failure. | |
1442 | ||
1443 | =item tcflush | |
1444 | ||
4755096e | 1445 | This is similar to the C function C<tcflush()> for flushing |
cc767757 | 1446 | the I/O buffers of its argument stream. |
37120919 AD |
1447 | |
1448 | Returns C<undef> on failure. | |
1449 | ||
1450 | =item tcgetpgrp | |
1451 | ||
4755096e GS |
1452 | This is identical to the C function C<tcgetpgrp()> for returning the |
1453 | process group identifier of the foreground process group of the controlling | |
1454 | terminal. | |
37120919 AD |
1455 | |
1456 | =item tcsendbreak | |
1457 | ||
4755096e GS |
1458 | This is similar to the C function C<tcsendbreak()> for sending |
1459 | a break on its argument stream. | |
37120919 AD |
1460 | |
1461 | Returns C<undef> on failure. | |
1462 | ||
1463 | =item tcsetpgrp | |
1464 | ||
4755096e GS |
1465 | This is similar to the C function C<tcsetpgrp()> for setting the |
1466 | process group identifier of the foreground process group of the controlling | |
1467 | terminal. | |
37120919 AD |
1468 | |
1469 | Returns C<undef> on failure. | |
1470 | ||
1471 | =item time | |
1472 | ||
4755096e GS |
1473 | This is identical to Perl's builtin C<time()> function |
1474 | for returning the number of seconds since the epoch | |
1475 | (whatever it is for the system), see L<perlfunc/time>. | |
37120919 AD |
1476 | |
1477 | =item times | |
1478 | ||
1479 | The times() function returns elapsed realtime since some point in the past | |
1480 | (such as system startup), user and system times for this process, and user | |
1481 | and system times used by child processes. All times are returned in clock | |
1482 | ticks. | |
1483 | ||
1484 | ($realtime, $user, $system, $cuser, $csystem) = POSIX::times(); | |
1485 | ||
1486 | Note: Perl's builtin C<times()> function returns four values, measured in | |
1487 | seconds. | |
1488 | ||
1489 | =item tmpfile | |
1490 | ||
4755096e | 1491 | Use method C<IO::File::new_tmpfile()> instead, or see L<File::Temp>. |
37120919 AD |
1492 | |
1493 | =item tmpnam | |
1494 | ||
1495 | Returns a name for a temporary file. | |
1496 | ||
1497 | $tmpfile = POSIX::tmpnam(); | |
1498 | ||
60cba15a DD |
1499 | For security reasons, which are probably detailed in your system's |
1500 | documentation for the C library tmpnam() function, this interface | |
1501 | should not be used; instead see L<File::Temp>. | |
4755096e | 1502 | |
37120919 AD |
1503 | =item tolower |
1504 | ||
4755096e GS |
1505 | This is identical to the C function, except that it can apply to a single |
1506 | character or to a whole string. Consider using the C<lc()> function, | |
1507 | see L<perlfunc/lc>, or the equivalent C<\L> operator inside doublequotish | |
1508 | strings. | |
37120919 AD |
1509 | |
1510 | =item toupper | |
1511 | ||
4755096e GS |
1512 | This is identical to the C function, except that it can apply to a single |
1513 | character or to a whole string. Consider using the C<uc()> function, | |
1514 | see L<perlfunc/uc>, or the equivalent C<\U> operator inside doublequotish | |
1515 | strings. | |
37120919 AD |
1516 | |
1517 | =item ttyname | |
1518 | ||
4755096e GS |
1519 | This is identical to the C function C<ttyname()> for returning the |
1520 | name of the current terminal. | |
37120919 AD |
1521 | |
1522 | =item tzname | |
1523 | ||
cb1a09d0 AD |
1524 | Retrieves the time conversion information from the C<tzname> variable. |
1525 | ||
1526 | POSIX::tzset(); | |
1527 | ($std, $dst) = POSIX::tzname(); | |
37120919 AD |
1528 | |
1529 | =item tzset | |
1530 | ||
4755096e GS |
1531 | This is identical to the C function C<tzset()> for setting |
1532 | the current timezone based on the environment variable C<TZ>, | |
1533 | to be used by C<ctime()>, C<localtime()>, C<mktime()>, and C<strftime()> | |
1534 | functions. | |
37120919 AD |
1535 | |
1536 | =item umask | |
1537 | ||
4755096e GS |
1538 | This is identical to Perl's builtin C<umask()> function |
1539 | for setting (and querying) the file creation permission mask, | |
1540 | see L<perlfunc/umask>. | |
37120919 AD |
1541 | |
1542 | =item uname | |
1543 | ||
cb1a09d0 AD |
1544 | Get name of current operating system. |
1545 | ||
4755096e GS |
1546 | ($sysname, $nodename, $release, $version, $machine) = POSIX::uname(); |
1547 | ||
1548 | Note that the actual meanings of the various fields are not | |
1549 | that well standardized, do not expect any great portability. | |
1550 | The C<$sysname> might be the name of the operating system, | |
1551 | the C<$nodename> might be the name of the host, the C<$release> | |
1552 | might be the (major) release number of the operating system, | |
1553 | the C<$version> might be the (minor) release number of the | |
1554 | operating system, and the C<$machine> might be a hardware identifier. | |
1555 | Maybe. | |
37120919 AD |
1556 | |
1557 | =item ungetc | |
1558 | ||
28757baa | 1559 | Use method C<IO::Handle::ungetc()> instead. |
37120919 AD |
1560 | |
1561 | =item unlink | |
1562 | ||
4755096e GS |
1563 | This is identical to Perl's builtin C<unlink()> function |
1564 | for removing files, see L<perlfunc/unlink>. | |
37120919 AD |
1565 | |
1566 | =item utime | |
1567 | ||
4755096e GS |
1568 | This is identical to Perl's builtin C<utime()> function |
1569 | for changing the time stamps of files and directories, | |
1570 | see L<perlfunc/utime>. | |
37120919 AD |
1571 | |
1572 | =item vfprintf | |
1573 | ||
4755096e | 1574 | vfprintf() is C-specific, see L<perlfunc/printf> instead. |
37120919 AD |
1575 | |
1576 | =item vprintf | |
1577 | ||
4755096e | 1578 | vprintf() is C-specific, see L<perlfunc/printf> instead. |
37120919 AD |
1579 | |
1580 | =item vsprintf | |
1581 | ||
4755096e | 1582 | vsprintf() is C-specific, see L<perlfunc/sprintf> instead. |
37120919 AD |
1583 | |
1584 | =item wait | |
1585 | ||
4755096e GS |
1586 | This is identical to Perl's builtin C<wait()> function, |
1587 | see L<perlfunc/wait>. | |
37120919 AD |
1588 | |
1589 | =item waitpid | |
1590 | ||
cb1a09d0 | 1591 | Wait for a child process to change state. This is identical to Perl's |
4755096e | 1592 | builtin C<waitpid()> function, see L<perlfunc/waitpid>. |
cb1a09d0 | 1593 | |
2ac1ef3d | 1594 | $pid = POSIX::waitpid( -1, POSIX::WNOHANG ); |
cb1a09d0 | 1595 | print "status = ", ($? / 256), "\n"; |
37120919 AD |
1596 | |
1597 | =item wcstombs | |
1598 | ||
cb1a09d0 | 1599 | This is identical to the C function C<wcstombs()>. |
4755096e GS |
1600 | Perl does not have any support for the wide and multibyte |
1601 | characters of the C standards, so this might be a rather | |
1602 | useless function. | |
37120919 AD |
1603 | |
1604 | =item wctomb | |
1605 | ||
cb1a09d0 | 1606 | This is identical to the C function C<wctomb()>. |
4755096e GS |
1607 | Perl does not have any support for the wide and multibyte |
1608 | characters of the C standards, so this might be a rather | |
1609 | useless function. | |
37120919 AD |
1610 | |
1611 | =item write | |
1612 | ||
cb1a09d0 AD |
1613 | Write to a file. This uses file descriptors such as those obtained by |
1614 | calling C<POSIX::open>. | |
1615 | ||
1616 | $fd = POSIX::open( "foo", &POSIX::O_WRONLY ); | |
1617 | $buf = "hello"; | |
1618 | $bytes = POSIX::write( $b, $buf, 5 ); | |
37120919 AD |
1619 | |
1620 | Returns C<undef> on failure. | |
1621 | ||
4755096e GS |
1622 | See also L<perlfunc/syswrite>. |
1623 | ||
37120919 AD |
1624 | =back |
1625 | ||
1626 | =head1 CLASSES | |
1627 | ||
37120919 AD |
1628 | =head2 POSIX::SigAction |
1629 | ||
1630 | =over 8 | |
1631 | ||
1632 | =item new | |
1633 | ||
cb1a09d0 AD |
1634 | Creates a new C<POSIX::SigAction> object which corresponds to the C |
1635 | C<struct sigaction>. This object will be destroyed automatically when it is | |
1636 | no longer needed. The first parameter is the fully-qualified name of a sub | |
1637 | which is a signal-handler. The second parameter is a C<POSIX::SigSet> | |
28757baa | 1638 | object, it defaults to the empty set. The third parameter contains the |
1639 | C<sa_flags>, it defaults to 0. | |
cb1a09d0 | 1640 | |
28757baa | 1641 | $sigset = POSIX::SigSet->new(SIGINT, SIGQUIT); |
cb1a09d0 AD |
1642 | $sigaction = POSIX::SigAction->new( 'main::handler', $sigset, &POSIX::SA_NOCLDSTOP ); |
1643 | ||
1644 | This C<POSIX::SigAction> object should be used with the C<POSIX::sigaction()> | |
1645 | function. | |
37120919 AD |
1646 | |
1647 | =back | |
1648 | ||
557c0de7 BD |
1649 | =over 8 |
1650 | ||
1651 | =item handler | |
1652 | ||
1653 | =item mask | |
1654 | ||
1655 | =item flags | |
1656 | ||
1657 | accessor functions to get/set the values of a SigAction object. | |
1658 | ||
1659 | $sigset = $sigaction->mask; | |
1660 | $sigaction->flags(&POSIX::SA_RESTART); | |
1661 | ||
1662 | =back | |
1663 | ||
37120919 AD |
1664 | =head2 POSIX::SigSet |
1665 | ||
1666 | =over 8 | |
1667 | ||
1668 | =item new | |
1669 | ||
1670 | Create a new SigSet object. This object will be destroyed automatically | |
1671 | when it is no longer needed. Arguments may be supplied to initialize the | |
1672 | set. | |
1673 | ||
1674 | Create an empty set. | |
1675 | ||
1676 | $sigset = POSIX::SigSet->new; | |
1677 | ||
1678 | Create a set with SIGUSR1. | |
1679 | ||
1680 | $sigset = POSIX::SigSet->new( &POSIX::SIGUSR1 ); | |
1681 | ||
1682 | =item addset | |
1683 | ||
1684 | Add a signal to a SigSet object. | |
1685 | ||
1686 | $sigset->addset( &POSIX::SIGUSR2 ); | |
1687 | ||
1688 | Returns C<undef> on failure. | |
1689 | ||
1690 | =item delset | |
1691 | ||
1692 | Remove a signal from the SigSet object. | |
1693 | ||
1694 | $sigset->delset( &POSIX::SIGUSR2 ); | |
1695 | ||
1696 | Returns C<undef> on failure. | |
1697 | ||
1698 | =item emptyset | |
1699 | ||
1700 | Initialize the SigSet object to be empty. | |
1701 | ||
1702 | $sigset->emptyset(); | |
1703 | ||
1704 | Returns C<undef> on failure. | |
1705 | ||
1706 | =item fillset | |
1707 | ||
1708 | Initialize the SigSet object to include all signals. | |
1709 | ||
1710 | $sigset->fillset(); | |
1711 | ||
1712 | Returns C<undef> on failure. | |
1713 | ||
1714 | =item ismember | |
1715 | ||
1716 | Tests the SigSet object to see if it contains a specific signal. | |
1717 | ||
1718 | if( $sigset->ismember( &POSIX::SIGUSR1 ) ){ | |
1719 | print "contains SIGUSR1\n"; | |
1720 | } | |
1721 | ||
1722 | =back | |
1723 | ||
1724 | =head2 POSIX::Termios | |
1725 | ||
1726 | =over 8 | |
1727 | ||
1728 | =item new | |
1729 | ||
1730 | Create a new Termios object. This object will be destroyed automatically | |
55d729e4 GS |
1731 | when it is no longer needed. A Termios object corresponds to the termios |
1732 | C struct. new() mallocs a new one, getattr() fills it from a file descriptor, | |
1733 | and setattr() sets a file descriptor's parameters to match Termios' contents. | |
37120919 AD |
1734 | |
1735 | $termios = POSIX::Termios->new; | |
1736 | ||
1737 | =item getattr | |
1738 | ||
cb1a09d0 AD |
1739 | Get terminal control attributes. |
1740 | ||
1741 | Obtain the attributes for stdin. | |
1742 | ||
1743 | $termios->getattr() | |
1744 | ||
1745 | Obtain the attributes for stdout. | |
1746 | ||
1747 | $termios->getattr( 1 ) | |
37120919 AD |
1748 | |
1749 | Returns C<undef> on failure. | |
1750 | ||
1751 | =item getcc | |
1752 | ||
1753 | Retrieve a value from the c_cc field of a termios object. The c_cc field is | |
1754 | an array so an index must be specified. | |
1755 | ||
1756 | $c_cc[1] = $termios->getcc(1); | |
1757 | ||
1758 | =item getcflag | |
1759 | ||
1760 | Retrieve the c_cflag field of a termios object. | |
1761 | ||
1762 | $c_cflag = $termios->getcflag; | |
1763 | ||
1764 | =item getiflag | |
1765 | ||
1766 | Retrieve the c_iflag field of a termios object. | |
1767 | ||
1768 | $c_iflag = $termios->getiflag; | |
1769 | ||
1770 | =item getispeed | |
1771 | ||
1772 | Retrieve the input baud rate. | |
1773 | ||
1774 | $ispeed = $termios->getispeed; | |
1775 | ||
1776 | =item getlflag | |
1777 | ||
1778 | Retrieve the c_lflag field of a termios object. | |
1779 | ||
1780 | $c_lflag = $termios->getlflag; | |
1781 | ||
1782 | =item getoflag | |
1783 | ||
1784 | Retrieve the c_oflag field of a termios object. | |
1785 | ||
1786 | $c_oflag = $termios->getoflag; | |
1787 | ||
1788 | =item getospeed | |
1789 | ||
1790 | Retrieve the output baud rate. | |
1791 | ||
1792 | $ospeed = $termios->getospeed; | |
1793 | ||
1794 | =item setattr | |
1795 | ||
cb1a09d0 AD |
1796 | Set terminal control attributes. |
1797 | ||
1798 | Set attributes immediately for stdout. | |
1799 | ||
1800 | $termios->setattr( 1, &POSIX::TCSANOW ); | |
37120919 AD |
1801 | |
1802 | Returns C<undef> on failure. | |
1803 | ||
1804 | =item setcc | |
1805 | ||
1806 | Set a value in the c_cc field of a termios object. The c_cc field is an | |
1807 | array so an index must be specified. | |
1808 | ||
6b7a6f50 | 1809 | $termios->setcc( &POSIX::VEOF, 1 ); |
37120919 AD |
1810 | |
1811 | =item setcflag | |
1812 | ||
1813 | Set the c_cflag field of a termios object. | |
1814 | ||
55d729e4 | 1815 | $termios->setcflag( $c_cflag | &POSIX::CLOCAL ); |
37120919 AD |
1816 | |
1817 | =item setiflag | |
1818 | ||
1819 | Set the c_iflag field of a termios object. | |
1820 | ||
55d729e4 | 1821 | $termios->setiflag( $c_iflag | &POSIX::BRKINT ); |
37120919 AD |
1822 | |
1823 | =item setispeed | |
1824 | ||
1825 | Set the input baud rate. | |
1826 | ||
1827 | $termios->setispeed( &POSIX::B9600 ); | |
1828 | ||
1829 | Returns C<undef> on failure. | |
1830 | ||
1831 | =item setlflag | |
1832 | ||
1833 | Set the c_lflag field of a termios object. | |
1834 | ||
55d729e4 | 1835 | $termios->setlflag( $c_lflag | &POSIX::ECHO ); |
37120919 AD |
1836 | |
1837 | =item setoflag | |
1838 | ||
1839 | Set the c_oflag field of a termios object. | |
1840 | ||
55d729e4 | 1841 | $termios->setoflag( $c_oflag | &POSIX::OPOST ); |
37120919 AD |
1842 | |
1843 | =item setospeed | |
1844 | ||
1845 | Set the output baud rate. | |
1846 | ||
1847 | $termios->setospeed( &POSIX::B9600 ); | |
1848 | ||
1849 | Returns C<undef> on failure. | |
1850 | ||
1851 | =item Baud rate values | |
1852 | ||
1853 | B38400 B75 B200 B134 B300 B1800 B150 B0 B19200 B1200 B9600 B600 B4800 B50 B2400 B110 | |
1854 | ||
1855 | =item Terminal interface values | |
1856 | ||
1857 | TCSADRAIN TCSANOW TCOON TCIOFLUSH TCOFLUSH TCION TCIFLUSH TCSAFLUSH TCIOFF TCOOFF | |
1858 | ||
1859 | =item c_cc field values | |
1860 | ||
1861 | VEOF VEOL VERASE VINTR VKILL VQUIT VSUSP VSTART VSTOP VMIN VTIME NCCS | |
1862 | ||
1863 | =item c_cflag field values | |
1864 | ||
1865 | CLOCAL CREAD CSIZE CS5 CS6 CS7 CS8 CSTOPB HUPCL PARENB PARODD | |
1866 | ||
1867 | =item c_iflag field values | |
1868 | ||
1869 | BRKINT ICRNL IGNBRK IGNCR IGNPAR INLCR INPCK ISTRIP IXOFF IXON PARMRK | |
1870 | ||
1871 | =item c_lflag field values | |
1872 | ||
1873 | ECHO ECHOE ECHOK ECHONL ICANON IEXTEN ISIG NOFLSH TOSTOP | |
1874 | ||
1875 | =item c_oflag field values | |
1876 | ||
1877 | OPOST | |
1878 | ||
1879 | =back | |
1880 | ||
1881 | =head1 PATHNAME CONSTANTS | |
1882 | ||
1883 | =over 8 | |
1884 | ||
1885 | =item Constants | |
1886 | ||
1887 | _PC_CHOWN_RESTRICTED _PC_LINK_MAX _PC_MAX_CANON _PC_MAX_INPUT _PC_NAME_MAX _PC_NO_TRUNC _PC_PATH_MAX _PC_PIPE_BUF _PC_VDISABLE | |
1888 | ||
1889 | =back | |
1890 | ||
1891 | =head1 POSIX CONSTANTS | |
1892 | ||
1893 | =over 8 | |
1894 | ||
1895 | =item Constants | |
1896 | ||
1897 | _POSIX_ARG_MAX _POSIX_CHILD_MAX _POSIX_CHOWN_RESTRICTED _POSIX_JOB_CONTROL _POSIX_LINK_MAX _POSIX_MAX_CANON _POSIX_MAX_INPUT _POSIX_NAME_MAX _POSIX_NGROUPS_MAX _POSIX_NO_TRUNC _POSIX_OPEN_MAX _POSIX_PATH_MAX _POSIX_PIPE_BUF _POSIX_SAVED_IDS _POSIX_SSIZE_MAX _POSIX_STREAM_MAX _POSIX_TZNAME_MAX _POSIX_VDISABLE _POSIX_VERSION | |
1898 | ||
1899 | =back | |
1900 | ||
1901 | =head1 SYSTEM CONFIGURATION | |
1902 | ||
1903 | =over 8 | |
1904 | ||
1905 | =item Constants | |
1906 | ||
d61b6859 | 1907 | _SC_ARG_MAX _SC_CHILD_MAX _SC_CLK_TCK _SC_JOB_CONTROL _SC_NGROUPS_MAX _SC_OPEN_MAX _SC_PAGESIZE _SC_SAVED_IDS _SC_STREAM_MAX _SC_TZNAME_MAX _SC_VERSION |
37120919 AD |
1908 | |
1909 | =back | |
1910 | ||
1911 | =head1 ERRNO | |
1912 | ||
1913 | =over 8 | |
1914 | ||
1915 | =item Constants | |
1916 | ||
774d564b | 1917 | E2BIG EACCES EADDRINUSE EADDRNOTAVAIL EAFNOSUPPORT EAGAIN EALREADY EBADF |
1918 | EBUSY ECHILD ECONNABORTED ECONNREFUSED ECONNRESET EDEADLK EDESTADDRREQ | |
1919 | EDOM EDQUOT EEXIST EFAULT EFBIG EHOSTDOWN EHOSTUNREACH EINPROGRESS EINTR | |
1920 | EINVAL EIO EISCONN EISDIR ELOOP EMFILE EMLINK EMSGSIZE ENAMETOOLONG | |
1921 | ENETDOWN ENETRESET ENETUNREACH ENFILE ENOBUFS ENODEV ENOENT ENOEXEC | |
1922 | ENOLCK ENOMEM ENOPROTOOPT ENOSPC ENOSYS ENOTBLK ENOTCONN ENOTDIR | |
1923 | ENOTEMPTY ENOTSOCK ENOTTY ENXIO EOPNOTSUPP EPERM EPFNOSUPPORT EPIPE | |
1924 | EPROCLIM EPROTONOSUPPORT EPROTOTYPE ERANGE EREMOTE ERESTART EROFS | |
1925 | ESHUTDOWN ESOCKTNOSUPPORT ESPIPE ESRCH ESTALE ETIMEDOUT ETOOMANYREFS | |
1926 | ETXTBSY EUSERS EWOULDBLOCK EXDEV | |
37120919 AD |
1927 | |
1928 | =back | |
1929 | ||
1930 | =head1 FCNTL | |
1931 | ||
1932 | =over 8 | |
1933 | ||
1934 | =item Constants | |
1935 | ||
1936 | FD_CLOEXEC F_DUPFD F_GETFD F_GETFL F_GETLK F_OK F_RDLCK F_SETFD F_SETFL F_SETLK F_SETLKW F_UNLCK F_WRLCK O_ACCMODE O_APPEND O_CREAT O_EXCL O_NOCTTY O_NONBLOCK O_RDONLY O_RDWR O_TRUNC O_WRONLY | |
1937 | ||
1938 | =back | |
1939 | ||
1940 | =head1 FLOAT | |
1941 | ||
1942 | =over 8 | |
1943 | ||
1944 | =item Constants | |
1945 | ||
1946 | DBL_DIG DBL_EPSILON DBL_MANT_DIG DBL_MAX DBL_MAX_10_EXP DBL_MAX_EXP DBL_MIN DBL_MIN_10_EXP DBL_MIN_EXP FLT_DIG FLT_EPSILON FLT_MANT_DIG FLT_MAX FLT_MAX_10_EXP FLT_MAX_EXP FLT_MIN FLT_MIN_10_EXP FLT_MIN_EXP FLT_RADIX FLT_ROUNDS LDBL_DIG LDBL_EPSILON LDBL_MANT_DIG LDBL_MAX LDBL_MAX_10_EXP LDBL_MAX_EXP LDBL_MIN LDBL_MIN_10_EXP LDBL_MIN_EXP | |
1947 | ||
1948 | =back | |
1949 | ||
1950 | =head1 LIMITS | |
1951 | ||
1952 | =over 8 | |
1953 | ||
1954 | =item Constants | |
1955 | ||
1956 | ARG_MAX CHAR_BIT CHAR_MAX CHAR_MIN CHILD_MAX INT_MAX INT_MIN LINK_MAX LONG_MAX LONG_MIN MAX_CANON MAX_INPUT MB_LEN_MAX NAME_MAX NGROUPS_MAX OPEN_MAX PATH_MAX PIPE_BUF SCHAR_MAX SCHAR_MIN SHRT_MAX SHRT_MIN SSIZE_MAX STREAM_MAX TZNAME_MAX UCHAR_MAX UINT_MAX ULONG_MAX USHRT_MAX | |
1957 | ||
1958 | =back | |
1959 | ||
1960 | =head1 LOCALE | |
1961 | ||
1962 | =over 8 | |
1963 | ||
1964 | =item Constants | |
1965 | ||
1966 | LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME | |
1967 | ||
1968 | =back | |
1969 | ||
1970 | =head1 MATH | |
1971 | ||
1972 | =over 8 | |
1973 | ||
1974 | =item Constants | |
1975 | ||
1976 | HUGE_VAL | |
1977 | ||
1978 | =back | |
1979 | ||
1980 | =head1 SIGNAL | |
1981 | ||
1982 | =over 8 | |
1983 | ||
1984 | =item Constants | |
1985 | ||
774d564b | 1986 | SA_NOCLDSTOP SA_NOCLDWAIT SA_NODEFER SA_ONSTACK SA_RESETHAND SA_RESTART |
1987 | SA_SIGINFO SIGABRT SIGALRM SIGCHLD SIGCONT SIGFPE SIGHUP SIGILL SIGINT | |
1988 | SIGKILL SIGPIPE SIGQUIT SIGSEGV SIGSTOP SIGTERM SIGTSTP SIGTTIN SIGTTOU | |
1989 | SIGUSR1 SIGUSR2 SIG_BLOCK SIG_DFL SIG_ERR SIG_IGN SIG_SETMASK | |
1990 | SIG_UNBLOCK | |
37120919 AD |
1991 | |
1992 | =back | |
1993 | ||
1994 | =head1 STAT | |
1995 | ||
1996 | =over 8 | |
1997 | ||
1998 | =item Constants | |
1999 | ||
2000 | S_IRGRP S_IROTH S_IRUSR S_IRWXG S_IRWXO S_IRWXU S_ISGID S_ISUID S_IWGRP S_IWOTH S_IWUSR S_IXGRP S_IXOTH S_IXUSR | |
2001 | ||
2002 | =item Macros | |
2003 | ||
2004 | S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISREG | |
2005 | ||
2006 | =back | |
2007 | ||
2008 | =head1 STDLIB | |
2009 | ||
2010 | =over 8 | |
2011 | ||
2012 | =item Constants | |
2013 | ||
2014 | EXIT_FAILURE EXIT_SUCCESS MB_CUR_MAX RAND_MAX | |
2015 | ||
2016 | =back | |
2017 | ||
2018 | =head1 STDIO | |
2019 | ||
2020 | =over 8 | |
2021 | ||
2022 | =item Constants | |
2023 | ||
c07a80fd | 2024 | BUFSIZ EOF FILENAME_MAX L_ctermid L_cuserid L_tmpname TMP_MAX |
37120919 AD |
2025 | |
2026 | =back | |
2027 | ||
2028 | =head1 TIME | |
2029 | ||
2030 | =over 8 | |
2031 | ||
2032 | =item Constants | |
2033 | ||
2034 | CLK_TCK CLOCKS_PER_SEC | |
2035 | ||
2036 | =back | |
2037 | ||
2038 | =head1 UNISTD | |
2039 | ||
2040 | =over 8 | |
2041 | ||
2042 | =item Constants | |
2043 | ||
b250498f | 2044 | R_OK SEEK_CUR SEEK_END SEEK_SET STDIN_FILENO STDOUT_FILENO STDERR_FILENO W_OK X_OK |
37120919 AD |
2045 | |
2046 | =back | |
2047 | ||
2048 | =head1 WAIT | |
2049 | ||
2050 | =over 8 | |
2051 | ||
2052 | =item Constants | |
2053 | ||
2054 | WNOHANG WUNTRACED | |
2055 | ||
9d6eb86e JH |
2056 | =over 16 |
2057 | ||
2058 | =item WNOHANG | |
2059 | ||
2060 | Do not suspend the calling process until a child process | |
2061 | changes state but instead return immediately. | |
2062 | ||
2063 | =item WUNTRACED | |
2064 | ||
2065 | Catch stopped child processes. | |
2066 | ||
2067 | =back | |
2068 | ||
37120919 AD |
2069 | =item Macros |
2070 | ||
2071 | WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG WIFSTOPPED WSTOPSIG | |
2072 | ||
9d6eb86e JH |
2073 | =over 16 |
2074 | ||
2075 | =item WIFEXITED | |
2076 | ||
2077 | WIFEXITED($?) returns true if the child process exited normally | |
2078 | (C<exit()> or by falling off the end of C<main()>) | |
2079 | ||
2080 | =item WEXITSTATUS | |
2081 | ||
2082 | WEXITSTATUS($?) returns the normal exit status of the child process | |
2083 | (only meaningful if WIFEXITED($?) is true) | |
2084 | ||
2085 | =item WIFSIGNALED | |
2086 | ||
2087 | WIFSIGNALED($?) returns true if the child process terminated because | |
2088 | of a signal | |
2089 | ||
2090 | =item WTERMSIG | |
2091 | ||
2092 | WTERMSIG($?) returns the signal the child process terminated for | |
2093 | (only meaningful if WIFSIGNALED($?) is true) | |
2094 | ||
2095 | =item WIFSTOPPED | |
2096 | ||
2097 | WIFSTOPPED($?) returns true if the child process is currently stopped | |
2098 | (can happen only if you specified the WUNTRACED flag to waitpid()) | |
2099 | ||
2100 | =item WSTOPSIG | |
2101 | ||
2102 | WSTOPSIG($?) returns the signal the child process was stopped for | |
2103 | (only meaningful if WIFSTOPPED($?) is true) | |
2104 | ||
2105 | =back | |
2106 | ||
37120919 AD |
2107 | =back |
2108 |