| Commit | Line | Data |
|---|
| a0d0e21e |
1 | =head1 NAME |
| 2 | |
| 3 | POSIX - Perl interface to IEEE 1003.1 namespace |
| 4 | |
| 5 | =head1 SYNOPSIS |
| 6 | |
| 7 | use POSIX; |
| 8 | use POSIX 'strftime'; |
| 9 | |
| 10 | =head1 DESCRIPTION |
| 11 | |
| 12 | The POSIX module permits you to access all (or nearly all) the standard |
| 13 | POSIX 1003.1 identifiers. Things which are C<#defines> in C, like EINTR |
| 14 | or O_NDELAY, are automatically exported into your namespace. All |
| 15 | functions are only exported if you ask for them explicitly. Most likely |
| 16 | people will prefer to use the fully-qualified function names. |
| 17 | |
| 18 | To get a list of all the possible identifiers available to you--and |
| 19 | their semantics--you should pick up a 1003.1 spec, or look in the |
| 20 | F<POSIX.pm> module. |
| 21 | |
| 22 | =head1 EXAMPLES |
| 23 | |
| 748a9306 |
24 | printf "EINTR is %d\n", EINTR; |
| a0d0e21e |
25 | |
| 26 | POSIX::setsid(0); |
| 27 | |
| 28 | $fd = POSIX::open($path, O_CREAT|O_EXCL|O_WRONLY, 0644); |
| 29 | # note: that's a filedescriptor, *NOT* a filehandle |
| 30 | |
| 31 | =head1 NOTE |
| 32 | |
| 33 | The POSIX module is probably the most complex Perl module supplied with |
| 34 | the standard distribution. It incorporates autoloading, namespace games, |
| 35 | and dynamic loading of code that's in Perl, C, or both. It's a great |
| 36 | source of wisdom. |
| 37 | |
| 38 | =head1 CAVEATS |
| 39 | |
| 40 | A few functions are not implemented because they are C specific. If you |
| 41 | attempt to call these, they will print a message telling you that they |
| 748a9306 |
42 | aren't implemented, and suggest using the Perl equivalent should one |
| 43 | exist. For example, trying to access the setjmp() call will elicit the |
| a0d0e21e |
44 | message "setjmp() is C-specific: use eval {} instead". |
| 45 | |
| 46 | Furthermore, some evil vendors will claim 1003.1 compliance, but in fact |
| 47 | are not so: they will not pass the PCTS (POSIX Compliance Test Suites). |
| 48 | For example, one vendor may not define EDEADLK, or the semantics of the |
| 49 | errno values set by open(2) might not be quite right. Perl does not |
| 50 | attempt to verify POSIX compliance. That means you can currently |
| 51 | successfully say "use POSIX", and then later in your program you find |
| 52 | that your vendor has been lax and there's no usable ICANON macro after |
| 53 | all. This could be construed to be a bug. |
projects / p5sagit/p5-mst-13.2.git / blame