3 POSIX - Perl interface to IEEE Std 1003.1
9 use POSIX qw(:errno_h :fcntl_h);
11 printf "EINTR is %d\n", EINTR;
13 $sess_id = POSIX::setsid();
15 $fd = POSIX::open($path, O_CREAT|O_EXCL|O_WRONLY, 0644);
16 # note: that's a filedescriptor, *NOT* a filehandle
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
22 interfaces. Things which are C<#defines> in C, like EINTR or O_NDELAY, are
23 automatically exported into your namespace. All functions are only exported
24 if you ask for them explicitly. Most likely people will prefer to use the
25 fully-qualified function names.
27 This document gives a condensed list of the features available in the POSIX
28 module. Consult your operating system's manpages for general information on
29 most features. Consult L<perlfunc> for functions which are noted as being
30 identical to Perl's builtin functions.
32 The first section describes POSIX functions from the 1003.1 specification.
33 The second section describes some classes for signal objects, TTY objects,
34 and other miscellaneous objects. The remaining sections list various
35 constants and macros in an organization which roughly follows IEEE Std
40 The POSIX module is probably the most complex Perl module supplied with
41 the standard distribution. It incorporates autoloading, namespace games,
42 and dynamic loading of code that's in Perl, C, or both. It's a great
47 A few functions are not implemented because they are C specific. If you
48 attempt to call these, they will print a message telling you that they
49 aren't implemented, and suggest using the Perl equivalent should one
50 exist. For example, trying to access the setjmp() call will elicit the
51 message "setjmp() is C-specific: use eval {} instead".
53 Furthermore, some evil vendors will claim 1003.1 compliance, but in fact
54 are not so: they will not pass the PCTS (POSIX Compliance Test Suites).
55 For example, one vendor may not define EDEADLK, or the semantics of the
56 errno values set by open(2) might not be quite right. Perl does not
57 attempt to verify POSIX compliance. That means you can currently
58 successfully say "use POSIX", and then later in your program you find
59 that your vendor has been lax and there's no usable ICANON macro after
60 all. This could be construed to be a bug.
68 This is identical to the C function C<_exit()>. It exits the program
69 immediately which means among other things buffered I/O is B<not> flushed.
73 This is identical to the C function C<abort()>. It terminates the
74 process with a C<SIGABRT> signal unless caught by a signal handler or
75 if the handler does not return normally (it e.g. does a C<longjmp>).
79 This is identical to Perl's builtin C<abs()> function, returning
80 the absolute value of its numerical argument.
84 Determines the accessibility of a file.
86 if( POSIX::access( "/", &POSIX::R_OK ) ){
87 print "have read permission\n";
90 Returns C<undef> on failure. Note: do not use C<access()> for
91 security purposes. Between the C<access()> call and the operation
92 you are preparing for the permissions might change: a classic
97 This is identical to the C function C<acos()>, returning
98 the arcus cosine of its numerical argument. See also L<Math::Trig>.
102 This is identical to Perl's builtin C<alarm()> function,
103 either for arming or disarming the C<SIGARLM> timer.
107 This is identical to the C function C<asctime()>. It returns
110 "Fri Jun 2 18:22:13 2000\n\0"
112 and it is called thusly
114 $asctime = asctime($sec, $min, $hour, $mday, $mon, $year,
115 $wday, $yday, $isdst);
117 The C<$mon> is zero-based: January equals C<0>. The C<$year> is
118 1900-based: 2001 equals C<101>. The C<$wday>, C<$yday>, and C<$isdst>
119 default to zero (and the first two are usually ignored anyway).
123 This is identical to the C function C<asin()>, returning
124 the arcus sine of its numerical argument. See also L<Math::Trig>.
128 Unimplemented, but you can use L<perlfunc/die> and the L<Carp> module
129 to achieve similar things.
133 This is identical to the C function C<atan()>, returning the
134 arcus tangent of its numerical argument. See also L<Math::Trig>.
138 This is identical to Perl's builtin C<atan2()> function, returning
139 the arcus tangent defined by its two numerical arguments, the I<y>
140 coordinate and the I<x> coordinate. See also L<Math::Trig>.
144 atexit() is C-specific: use C<END {}> instead, see L<perlsub>.
148 atof() is C-specific. Perl converts strings to numbers transparently.
149 If you need to force a scalar to a number, add a zero to it.
153 atoi() is C-specific. Perl converts strings to numbers transparently.
154 If you need to force a scalar to a number, add a zero to it.
155 If you need to have just the integer part, see L<perlfunc/int>.
159 atol() is C-specific. Perl converts strings to numbers transparently.
160 If you need to force a scalar to a number, add a zero to it.
161 If you need to have just the integer part, see L<perlfunc/int>.
165 bsearch() not supplied. For doing binary search on wordlists,
170 calloc() is C-specific. Perl does memory management transparently.
174 This is identical to the C function C<ceil()>, returning the smallest
175 integer value greater than or equal to the given numerical argument.
179 This is identical to Perl's builtin C<chdir()> function, allowing
180 one to change the working (default) directory, see L<perlfunc/chdir>.
184 This is identical to Perl's builtin C<chmod()> function, allowing
185 one to change file and directory permissions, see L<perlfunc/chmod>.
189 This is identical to Perl's builtin C<chown()> function, allowing one
190 to change file and directory owners and groups, see L<perlfunc/chown>.
194 Use the method C<IO::Handle::clearerr()> instead, to reset the error
195 state (if any) and EOF state (if any) of the given stream.
199 This is identical to the C function C<clock()>, returning the
200 amount of spent processor time in microseconds.
204 Close the file. This uses file descriptors such as those obtained by calling
207 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
210 Returns C<undef> on failure.
212 See also L<perlfunc/close>.
216 This is identical to Perl's builtin C<closedir()> function for closing
217 a directory handle, see L<perlfunc/closedir>.
221 This is identical to Perl's builtin C<cos()> function, for returning
222 the cosine of its numerical argument, see L<perlfunc/cos>.
223 See also L<Math::Trig>.
227 This is identical to the C function C<cosh()>, for returning
228 the hyperbolic cosine of its numeric argument. See also L<Math::Trig>.
232 Create a new file. This returns a file descriptor like the ones returned by
233 C<POSIX::open>. Use C<POSIX::close> to close the file.
235 $fd = POSIX::creat( "foo", 0611 );
238 See also L<perlfunc/sysopen> and its C<O_CREAT> flag.
242 Generates the path name for the controlling terminal.
244 $path = POSIX::ctermid();
248 This is identical to the C function C<ctime()> and equivalent
249 to C<asctime(localtime(...))>, see L</asctime> and L</localtime>.
253 Get the login name of the owner of the current process.
255 $name = POSIX::cuserid();
259 This is identical to the C function C<difftime()>, for returning
260 the time difference (in seconds) between two times (as returned
261 by C<time()>), see L</time>.
265 div() is C-specific, use L<perlfunc/int> on the usual C</> division and
270 This is similar to the C function C<dup()>, for duplicating a file
273 This uses file descriptors such as those obtained by calling
276 Returns C<undef> on failure.
280 This is similar to the C function C<dup2()>, for duplicating a file
281 descriptor to an another known file descriptor.
283 This uses file descriptors such as those obtained by calling
286 Returns C<undef> on failure.
290 Returns the value of errno.
292 $errno = POSIX::errno();
294 This identical to the numerical values of the C<$!>, see L<perlvar/$ERRNO>.
298 execl() is C-specific, see L<perlfunc/exec>.
302 execle() is C-specific, see L<perlfunc/exec>.
306 execlp() is C-specific, see L<perlfunc/exec>.
310 execv() is C-specific, see L<perlfunc/exec>.
314 execve() is C-specific, see L<perlfunc/exec>.
318 execvp() is C-specific, see L<perlfunc/exec>.
322 This is identical to Perl's builtin C<exit()> function for exiting the
323 program, see L<perlfunc/exit>.
327 This is identical to Perl's builtin C<exp()> function for
328 returning the exponent (I<e>-based) of the numerical argument,
333 This is identical to Perl's builtin C<abs()> function for returning
334 the absolute value of the numerical argument, see L<perlfunc/abs>.
338 Use method C<IO::Handle::close()> instead, or see L<perlfunc/close>.
342 This is identical to Perl's builtin C<fcntl()> function,
343 see L<perlfunc/fcntl>.
347 Use method C<IO::Handle::new_from_fd()> instead, or see L<perlfunc/open>.
351 Use method C<IO::Handle::eof()> instead, or see L<perlfunc/eof>.
355 Use method C<IO::Handle::error()> instead.
359 Use method C<IO::Handle::flush()> instead.
360 See also L<perlvar/$OUTPUT_AUTOFLUSH>.
364 Use method C<IO::Handle::getc()> instead, or see L<perlfunc/read>.
368 Use method C<IO::Seekable::getpos()> instead, or see L<L/seek>.
372 Use method C<IO::Handle::gets()> instead. Similar to E<lt>E<gt>, also known
373 as L<perlfunc/readline>.
377 Use method C<IO::Handle::fileno()> instead, or see L<perlfunc/fileno>.
381 This is identical to the C function C<floor()>, returning the largest
382 integer value less than or equal to the numerical argument.
386 This is identical to the C function C<fmod()>.
390 It returns the remainder C<$r = $x - $n*$y>, where C<$n = trunc($x/$y)>.
391 The C<$r> has the same sign as C<$x> and magnitude (absolute value)
392 less than the magnitude of C<$y>.
396 Use method C<IO::File::open()> instead, or see L<perlfunc/open>.
400 This is identical to Perl's builtin C<fork()> function
401 for duplicating the current process, see L<perlfunc/fork>
402 and L<perlfork> if you are in Windows.
406 Retrieves the value of a configurable limit on a file or directory. This
407 uses file descriptors such as those obtained by calling C<POSIX::open>.
409 The following will determine the maximum length of the longest allowable
410 pathname on the filesystem which holds C</tmp/foo>.
412 $fd = POSIX::open( "/tmp/foo", &POSIX::O_RDONLY );
413 $path_max = POSIX::fpathconf( $fd, &POSIX::_PC_PATH_MAX );
415 Returns C<undef> on failure.
419 fprintf() is C-specific, see L<perlfunc/printf> instead.
423 fputc() is C-specific, see L<perlfunc/print> instead.
427 fputs() is C-specific, see L<perlfunc/print> instead.
431 fread() is C-specific, see L<perlfunc/read> instead.
435 free() is C-specific. Perl does memory management transparently.
439 freopen() is C-specific, see L<perlfunc/open> instead.
443 Return the mantissa and exponent of a floating-point number.
445 ($mantissa, $exponent) = POSIX::frexp( 1.234e56 );
449 fscanf() is C-specific, use E<lt>E<gt> and regular expressions instead.
453 Use method C<IO::Seekable::seek()> instead, or see L<perlfunc/seek>.
457 Use method C<IO::Seekable::setpos()> instead, or seek L<perlfunc/seek>.
461 Get file status. This uses file descriptors such as those obtained by
462 calling C<POSIX::open>. The data returned is identical to the data from
463 Perl's builtin C<stat> function.
465 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
466 @stats = POSIX::fstat( $fd );
470 Use method C<IO::Seekable::tell()> instead, or see L<perlfunc/tell>.
474 fwrite() is C-specific, see L<perlfunc/print> instead.
478 This is identical to Perl's builtin C<getc()> function,
479 see L<perlfunc/getc>.
483 Returns one character from STDIN. Identical to Perl's C<getc()>,
484 see L<perlfunc/getc>.
488 Returns the name of the current working directory.
493 Returns the effective group identifier. Similar to Perl' s builtin
494 variable C<$(>, see L<perlvar/$EGID>.
498 Returns the value of the specified enironment variable.
499 The same information is available through the C<%ENV> array.
503 Returns the effective user identifier. Identical to Perl's builtin C<$E<gt>>
504 variable, see L<perlvar/$EUID>.
508 Returns the user's real group identifier. Similar to Perl's builtin
509 variable C<$)>, see L<perlvar/$GID>.
513 This is identical to Perl's builtin C<getgrgid()> function for
514 returning group entries by group identifiers, see
515 L<perlfunc/getgrgid>.
519 This is identical to Perl's builtin C<getgrnam()> function for
520 returning group entries by group names, see L<perlfunc/getgrnam>.
524 Returns the ids of the user's supplementary groups. Similar to Perl's
525 builtin variable C<$)>, see L<perlvar/$GID>.
529 This is identical to Perl's builtin C<getlogin()> function for
530 returning the user name associated with the current session, see
531 L<perlfunc/getlogin>.
535 This is identical to Perl's builtin C<getpgrp()> function for
536 returning the prcess group identifier of the current process, see
541 Returns the process identifier. Identical to Perl's builtin
542 variable C<$$>, see L<perlvar/$PID>.
546 This is identical to Perl's builtin C<getppid()> function for
547 returning the process identifier of the parent process of the current
548 process , see L<perlfunc/getppid>.
552 This is identical to Perl's builtin C<getpwnam()> function for
553 returning user entries by user names, see L<perlfunc/getpwnam>.
557 This is identical to Perl's builtin C<getpwuid()> function for
558 returning user entries by user identifiers, see L<perlfunc/getpwuid>.
562 Returns one line from C<STDIN>, similar to E<lt>E<gt>, also known
563 as the C<readline()> function, see L<perlfunc/readline>.
565 B<NOTE>: if you have C programs that still use C<gets()>, be very
566 afraid. The C<gets()> function is a source of endless grief because
567 it has no buffer overrun checks. It should B<never> be used. The
568 C<fgets()> function should be preferred instead.
572 Returns the user's identifier. Identical to Perl's builtin C<$E<lt>> variable,
577 This is identical to Perl's builtin C<gmtime()> function for
578 converting seconds since the epoch to a date in Greenwich Mean Time,
579 see L<perlfunc/gmtime>.
583 This is identical to the C function, except that it can apply to a
584 single character or to a whole string. Note that locale settings may
585 affect what characters are considered C<isalnum>. Does not work on
586 Unicode characters code point 256 or higher. Consider using regular
587 expressions and the C</[[:alnum:]]/> construct instead, or possibly
588 the C</\w/> construct.
592 This is identical to the C function, except that it can apply to
593 a single character or to a whole string. Note that locale settings
594 may affect what characters are considered C<isalpha>. Does not work
595 on Unicode characters code point 256 or higher. Consider using regular
596 expressions and the C</[[:alpha:]]/> construct instead.
600 Returns a boolean indicating whether the specified filehandle is connected
601 to a tty. Similar to the C<-t> operator, see L<perlfunc/-X>.
605 This is identical to the C function, except that it can apply to
606 a single character or to a whole string. Note that locale settings
607 may affect what characters are considered C<iscntrl>. Does not work
608 on Unicode characters code point 256 or higher. Consider using regular
609 expressions and the C</[[:cntrl:]]/> construct instead.
613 This is identical to the C function, except that it can apply to
614 a single character or to a whole string. Note that locale settings
615 may affect what characters are considered C<isdigit> (unlikely, but
616 still possible). Does not work on Unicode characters code point 256
617 or higher. Consider using regular expressions and the C</[[:digit:]]/>
618 construct instead, or the C</\d/> construct.
622 This is identical to the C function, except that it can apply to
623 a single character or to a whole string. Note that locale settings
624 may affect what characters are considered C<isgraph>. Does not work
625 on Unicode characters code point 256 or higher. Consider using regular
626 expressions and the C</[[:graph:]]/> construct instead.
630 This is identical to the C function, except that it can apply to
631 a single character or to a whole string. Note that locale settings
632 may affect what characters are considered C<islower>. Does not work
633 on Unicode characters code point 256 or higher. Consider using regular
634 expressions and the C</[[:lower:]]/> construct instead. Do B<not> use
639 This is identical to the C function, except that it can apply to
640 a single character or to a whole string. Note that locale settings
641 may affect what characters are considered C<isprint>. Does not work
642 on Unicode characters code point 256 or higher. Consider using regular
643 expressions and the C</[[:print:]]/> construct instead.
647 This is identical to the C function, except that it can apply to
648 a single character or to a whole string. Note that locale settings
649 may affect what characters are considered C<ispunct>. Does not work
650 on Unicode characters code point 256 or higher. Consider using regular
651 expressions and the C</[[:punct:]]/> construct instead.
655 This is identical to the C function, except that it can apply to
656 a single character or to a whole string. Note that locale settings
657 may affect what characters are considered C<isspace>. Does not work
658 on Unicode characters code point 256 or higher. Consider using regular
659 expressions and the C</[[:space:]]/> construct instead, or the C</\s/>
660 construct. (Note that C</\s/> and C</[[:space:]]/> are slightly
661 different in that C</[[:space:]]/> can normally match a vertical tab,
662 while C</\s/> does not.)
666 This is identical to the C function, except that it can apply to
667 a single character or to a whole string. Note that locale settings
668 may affect what characters are considered C<isupper>. Does not work
669 on Unicode characters code point 256 or higher. Consider using regular
670 expressions and the C</[[:upper:]]/> construct instead. Do B<not> use
675 This is identical to the C function, except that it can apply to a single
676 character or to a whole string. Note that locale settings may affect what
677 characters are considered C<isxdigit> (unlikely, but still possible).
678 Does not work on Unicode characters code point 256 or higher.
679 Consider using regular expressions and the C</[[:xdigit:]]/>
680 construct instead, or simply C</[0-9a-f]/i>.
684 This is identical to Perl's builtin C<kill()> function for sending
685 signals to processes (often to terminate them), see L<perlfunc/kill>.
689 (For returning absolute values of long integers.)
690 labs() is C-specific, see L<perlfunc/abs> instead.
694 This is identical to the C function C<ldexp()>
695 for multiplying floating point numbers with powers of two.
697 $x_quadrupled = POSIX::ldexp($x, 2);
701 (For computing dividends of long integers.)
702 ldiv() is C-specific, use C</> and C<int()> instead.
706 This is identical to Perl's builtin C<link()> function
707 for creating hard links into files, see L<perlfunc/link>.
711 Get numeric formatting information. Returns a reference to a hash
712 containing the current locale formatting values.
714 Here is how to query the database for the B<de> (Deutsch or German) locale.
716 $loc = POSIX::setlocale( &POSIX::LC_ALL, "de" );
717 print "Locale = $loc\n";
718 $lconv = POSIX::localeconv();
719 print "decimal_point = ", $lconv->{decimal_point}, "\n";
720 print "thousands_sep = ", $lconv->{thousands_sep}, "\n";
721 print "grouping = ", $lconv->{grouping}, "\n";
722 print "int_curr_symbol = ", $lconv->{int_curr_symbol}, "\n";
723 print "currency_symbol = ", $lconv->{currency_symbol}, "\n";
724 print "mon_decimal_point = ", $lconv->{mon_decimal_point}, "\n";
725 print "mon_thousands_sep = ", $lconv->{mon_thousands_sep}, "\n";
726 print "mon_grouping = ", $lconv->{mon_grouping}, "\n";
727 print "positive_sign = ", $lconv->{positive_sign}, "\n";
728 print "negative_sign = ", $lconv->{negative_sign}, "\n";
729 print "int_frac_digits = ", $lconv->{int_frac_digits}, "\n";
730 print "frac_digits = ", $lconv->{frac_digits}, "\n";
731 print "p_cs_precedes = ", $lconv->{p_cs_precedes}, "\n";
732 print "p_sep_by_space = ", $lconv->{p_sep_by_space}, "\n";
733 print "n_cs_precedes = ", $lconv->{n_cs_precedes}, "\n";
734 print "n_sep_by_space = ", $lconv->{n_sep_by_space}, "\n";
735 print "p_sign_posn = ", $lconv->{p_sign_posn}, "\n";
736 print "n_sign_posn = ", $lconv->{n_sign_posn}, "\n";
740 This is identical to Perl's builtin C<localtime()> function for
741 converting seconds since the epoch to a date see L<perlfunc/localtime>.
745 This is identical to Perl's builtin C<log()> function,
746 returning the natural (I<e>-based) logarithm of the numerical argument,
751 This is identical to the C function C<log10()>,
752 returning the 10-base logarithm of the numerical argument.
755 sub log10 { log($_[0]) / log(10) }
759 sub log10 { log($_[0]) / 2.30258509299405 }
763 sub log10 { log($_[0]) * 0.434294481903252 }
767 longjmp() is C-specific: use L<perlfunc/die> instead.
771 Move the file's read/write position. This uses file descriptors such as
772 those obtained by calling C<POSIX::open>.
774 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
775 $off_t = POSIX::lseek( $fd, 0, &POSIX::SEEK_SET );
777 Returns C<undef> on failure.
781 malloc() is C-specific. Perl does memory management transparently.
785 This is identical to the C function C<mblen()>.
786 Perl does not have any support for the wide and multibyte
787 characters of the C standards, so this might be a rather
792 This is identical to the C function C<mbstowcs()>.
793 Perl does not have any support for the wide and multibyte
794 characters of the C standards, so this might be a rather
799 This is identical to the C function C<mbtowc()>.
800 Perl does not have any support for the wide and multibyte
801 characters of the C standards, so this might be a rather
806 memchr() is C-specific, see L<perlfunc/index> instead.
810 memcmp() is C-specific, use C<eq> instead, see L<perlop>.
814 memcpy() is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>.
818 memmove() is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>.
822 memset() is C-specific, use C<x> instead, see L<perlop>.
826 This is identical to Perl's builtin C<mkdir()> function
827 for creating directories, see L<perlfunc/mkdir>.
831 This is similar to the C function C<mkfifo()> for creating
834 if (mkfifo($path, $mode)) { ....
836 Returns C<undef> on failure. The C<$mode> is similar to the
837 mode of C<mkdir()>, see L<perlfunc/mkdir>.
841 Convert date/time info to a calendar time.
845 mktime(sec, min, hour, mday, mon, year, wday = 0, yday = 0, isdst = 0)
847 The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero.
848 I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
849 year (C<year>) is given in years since 1900. I.e. The year 1995 is 95; the
850 year 2001 is 101. Consult your system's C<mktime()> manpage for details
851 about these and the other arguments.
853 Calendar time for December 12, 1995, at 10:30 am.
855 $time_t = POSIX::mktime( 0, 30, 10, 12, 11, 95 );
856 print "Date = ", POSIX::ctime($time_t);
858 Returns C<undef> on failure.
862 Return the integral and fractional parts of a floating-point number.
864 ($fractional, $integral) = POSIX::modf( 3.14 );
868 This is similar to the C function C<nice()>, for changing
869 the scheduling preference of the current process. Positive
870 arguments mean more polite process, negative values more
871 needy process. Normal user processes can only be more polite.
873 Returns C<undef> on failure.
877 offsetof() is C-specific, you probably want to see L<perlfunc/pack> instead.
881 Open a file for reading for writing. This returns file descriptors, not
882 Perl filehandles. Use C<POSIX::close> to close the file.
884 Open a file read-only with mode 0666.
886 $fd = POSIX::open( "foo" );
888 Open a file for read and write.
890 $fd = POSIX::open( "foo", &POSIX::O_RDWR );
892 Open a file for write, with truncation.
894 $fd = POSIX::open( "foo", &POSIX::O_WRONLY | &POSIX::O_TRUNC );
896 Create a new file with mode 0640. Set up the file for writing.
898 $fd = POSIX::open( "foo", &POSIX::O_CREAT | &POSIX::O_WRONLY, 0640 );
900 Returns C<undef> on failure.
902 See also L<perlfunc/sysopen>.
906 Open a directory for reading.
908 $dir = POSIX::opendir( "/tmp" );
909 @files = POSIX::readdir( $dir );
910 POSIX::closedir( $dir );
912 Returns C<undef> on failure.
916 Retrieves the value of a configurable limit on a file or directory.
918 The following will determine the maximum length of the longest allowable
919 pathname on the filesystem which holds C</tmp>.
921 $path_max = POSIX::pathconf( "/tmp", &POSIX::_PC_PATH_MAX );
923 Returns C<undef> on failure.
927 This is similar to the C function C<pause()>, which suspends
928 the execution of the current process until a signal is received.
930 Returns C<undef> on failure.
934 This is identical to the C function C<perror()>, which outputs to the
935 standard error stream the specified message followed by ": " and the
936 current error string. Use the C<warn()> function and the C<$!>
937 variable instead, see L<perlfunc/warn> and L<perlvar/$ERRNO>.
941 Create an interprocess channel. This returns file descriptors like those
942 returned by C<POSIX::open>.
944 ($fd0, $fd1) = POSIX::pipe();
945 POSIX::write( $fd0, "hello", 5 );
946 POSIX::read( $fd1, $buf, 5 );
948 See also L<perlfunc/pipe>.
952 Computes C<$x> raised to the power C<$exponent>.
954 $ret = POSIX::pow( $x, $exponent );
956 You can also use the C<**> operator, see L<perlop>.
960 Formats and prints the specified arguments to STDOUT.
961 See also L<perlfunc/printf>.
965 putc() is C-specific, see L<perlfunc/print> instead.
969 putchar() is C-specific, see L<perlfunc/print> instead.
973 puts() is C-specific, see L<perlfunc/print> instead.
977 qsort() is C-specific, see L<perlfunc/sort> instead.
981 Sends the specified signal to the current process.
982 See also L<perlfunc/kill> and the C<$$> in L<perlvar/$PID>.
986 C<rand()> is non-portable, see L<perlfunc/rand> instead.
990 Read from a file. This uses file descriptors such as those obtained by
991 calling C<POSIX::open>. If the buffer C<$buf> is not large enough for the
992 read then Perl will extend it to make room for the request.
994 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
995 $bytes = POSIX::read( $fd, $buf, 3 );
997 Returns C<undef> on failure.
999 See also L<perlfunc/sysread>.
1003 This is identical to Perl's builtin C<readdir()> function
1004 for reading directory entries, see L<perlfunc/readdir>.
1008 realloc() is C-specific. Perl does memory management transparently.
1012 This is identical to Perl's builtin C<unlink()> function
1013 for removing files, see L<perlfunc/unlink>.
1017 This is identical to Perl's builtin C<rename()> function
1018 for renaming files, see L<perlfunc/rename>.
1022 Seeks to the beginning of the file.
1026 This is identical to Perl's builtin C<rewinddir()> function for
1027 rewinding directory entry streams, see L<perlfunc/rewinddir>.
1031 This is identical to Perl's builtin C<rmdir()> function
1032 for removing (empty) directories, see L<perlfunc/rmdir>.
1036 scanf() is C-specific, use E<lt>E<gt> and regular expressions instead,
1041 Sets the real group identifier and the effective group identifier for
1042 this process. Similar to assigning a value to the Perl's builtin
1043 C<$)> variable, see L<perlvar/$GID>, except that the latter
1044 will change only the real user identifier, and that the setgid()
1045 uses only a single numeric argument, as opposed to a space-separated
1050 C<setjmp()> is C-specific: use C<eval {}> instead,
1051 see L<perlfunc/eval>.
1055 Modifies and queries program's locale. The following examples assume
1057 use POSIX qw(setlocale LC_ALL LC_CTYPE);
1061 The following will set the traditional UNIX system locale behavior
1062 (the second argument C<"C">).
1064 $loc = setlocale( LC_ALL, "C" );
1066 The following will query the current LC_CTYPE category. (No second
1067 argument means 'query'.)
1069 $loc = setlocale( LC_CTYPE );
1071 The following will set the LC_CTYPE behaviour according to the locale
1072 environment variables (the second argument C<"">).
1073 Please see your systems C<setlocale(3)> documentation for the locale
1074 environment variables' meaning or consult L<perllocale>.
1076 $loc = setlocale( LC_CTYPE, "" );
1078 The following will set the LC_COLLATE behaviour to Argentinian
1079 Spanish. B<NOTE>: The naming and availability of locales depends on
1080 your operating system. Please consult L<perllocale> for how to find
1081 out which locales are available in your system.
1083 $loc = setlocale( LC_ALL, "es_AR.ISO8859-1" );
1087 This is similar to the C function C<setpgid()> for
1088 setting the process group identifier of the current process.
1090 Returns C<undef> on failure.
1094 This is identical to the C function C<setsid()> for
1095 setting the session identifier of the current process.
1099 Sets the real user identifier and the effective user identifier for
1100 this process. Similar to assigning a value to the Perl's builtin
1101 C<$E<lt>> variable, see L<perlvar/$UID>, except that the latter
1102 will change only the real user identifier.
1106 Detailed signal management. This uses C<POSIX::SigAction> objects for the
1107 C<action> and C<oldaction> arguments. Consult your system's C<sigaction>
1108 manpage for details.
1112 sigaction(sig, action, oldaction = 0)
1114 Returns C<undef> on failure.
1118 siglongjmp() is C-specific: use L<perlfunc/die> instead.
1122 Examine signals that are blocked and pending. This uses C<POSIX::SigSet>
1123 objects for the C<sigset> argument. Consult your system's C<sigpending>
1124 manpage for details.
1130 Returns C<undef> on failure.
1134 Change and/or examine calling process's signal mask. This uses
1135 C<POSIX::SigSet> objects for the C<sigset> and C<oldsigset> arguments.
1136 Consult your system's C<sigprocmask> manpage for details.
1140 sigprocmask(how, sigset, oldsigset = 0)
1142 Returns C<undef> on failure.
1146 C<sigsetjmp()> is C-specific: use C<eval {}> instead,
1147 see L<perlfunc/eval>.
1151 Install a signal mask and suspend process until signal arrives. This uses
1152 C<POSIX::SigSet> objects for the C<signal_mask> argument. Consult your
1153 system's C<sigsuspend> manpage for details.
1157 sigsuspend(signal_mask)
1159 Returns C<undef> on failure.
1163 This is identical to Perl's builtin C<sin()> function
1164 for returning the sine of the numerical argument,
1165 see L<perlfunc/sin>. See also L<Math::Trig>.
1169 This is identical to the C function C<sinh()>
1170 for returning the hyperbolic sine of the numerical argument.
1171 See also L<Math::Trig>.
1175 This is functionally identical to Perl's builtin C<sleep()> function
1176 for suspending the execution of the current for process for certain
1177 number of seconds, see L<perlfunc/sleep>. There is one signifanct
1178 difference, however: C<POSIX::sleep()> returns the number of
1179 B<unslept> seconds, while the C<CORE::sleep()> returns the
1180 number of slept seconds.
1184 This is similar to Perl's builtin C<sprintf()> function
1185 for returning a string that has the arguments formatted as requested,
1186 see L<perlfunc/sprintf>.
1190 This is identical to Perl's builtin C<sqrt()> function.
1191 for returning the square root of the numerical argument,
1192 see L<perlfunc/sqrt>.
1196 Give a seed the pseudorandom number generator, see L<perlfunc/srand>.
1200 sscanf() is C-specific, use regular expressions instead,
1205 This is identical to Perl's builtin C<stat()> function
1206 for retutning information about files and directories.
1210 strcat() is C-specific, use C<.=> instead, see L<perlop>.
1214 strchr() is C-specific, see L<perlfunc/index> instead.
1218 strcmp() is C-specific, use C<eq> or C<cmp> instead, see L<perlop>.
1222 This is identical to the C function C<strcoll()>
1223 for collating (comparing) strings transformed using
1224 the C<strxfrm()> function. Not really needed since
1225 Perl can do this transparently, see L<perllocale>.
1229 strcpy() is C-specific, use C<=> instead, see L<perlop>.
1233 strcspn() is C-specific, use regular expressions instead,
1238 Returns the error string for the specified errno.
1239 Identical to the string form of the C<$!>, see L<perlvar/$ERRNO>.
1243 Convert date and time information to string. Returns the string.
1247 strftime(fmt, sec, min, hour, mday, mon, year, wday = -1, yday = -1, isdst = -1)
1249 The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero.
1250 I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
1251 year (C<year>) is given in years since 1900. I.e., the year 1995 is 95; the
1252 year 2001 is 101. Consult your system's C<strftime()> manpage for details
1253 about these and the other arguments.
1255 If you want your code to be portable, your format (C<fmt>) argument
1256 should use only the conversion specifiers defined by the ANSI C
1257 standard (C89, to play safe). These are C<aAbBcdHIjmMpSUwWxXyYZ%>.
1258 But even then, the B<results> of some of the conversion specifiers are
1259 non-portable. For example, the specifiers C<aAbBcpZ> change according
1260 to the locale settings of the user, and both how to set locales (the
1261 locale names) and what output to expect are non-standard.
1262 The specifier C<c> changes according to the timezone settings of the
1263 user and the timezone computation rules of the operating system.
1264 The C<Z> specifier is notoriously unportable since the names of
1265 timezones are non-standard. Sticking to the numeric specifiers is the
1268 The given arguments are made consistent as though by calling
1269 C<mktime()> before calling your system's C<strftime()> function,
1270 except that the C<isdst> value is not affected.
1272 The string for Tuesday, December 12, 1995.
1274 $str = POSIX::strftime( "%A, %B %d, %Y", 0, 0, 0, 12, 11, 95, 2 );
1279 strlen() is C-specific, use C<length()> instead, see L<perlfunc/length>.
1283 strncat() is C-specific, use C<.=> instead, see L<perlop>.
1287 strncmp() is C-specific, use C<eq> instead, see L<perlop>.
1291 strncpy() is C-specific, use C<=> instead, see L<perlop>.
1295 strpbrk() is C-specific, use regular expressions instead,
1300 strrchr() is C-specific, see L<perlfunc/rindex> instead.
1304 strspn() is C-specific, use regular expressions instead,
1309 This is identical to Perl's builtin C<index()> function,
1310 see L<perlfunc/index>.
1314 String to double translation. Returns the parsed number and the number
1315 of characters in the unparsed portion of the string. Truly
1316 POSIX-compliant systems set $! ($ERRNO) to indicate a translation
1317 error, so clear $! before calling strtod. However, non-POSIX systems
1318 may not check for overflow, and therefore will never set $!.
1320 strtod should respect any POSIX I<setlocale()> settings.
1322 To parse a string $str as a floating point number use
1325 ($num, $n_unparsed) = POSIX::strtod($str);
1327 The second returned item and $! can be used to check for valid input:
1329 if (($str eq '') || ($n_unparsed != 0) || !$!) {
1330 die "Non-numeric input $str" . $! ? ": $!\n" : "\n";
1333 When called in a scalar context strtod returns the parsed number.
1337 strtok() is C-specific, use regular expressions instead, see
1338 L<perlre>, or L<perlfunc/split>.
1342 String to (long) integer translation. Returns the parsed number and
1343 the number of characters in the unparsed portion of the string. Truly
1344 POSIX-compliant systems set $! ($ERRNO) to indicate a translation
1345 error, so clear $! before calling strtol. However, non-POSIX systems
1346 may not check for overflow, and therefore will never set $!.
1348 strtol should respect any POSIX I<setlocale()> settings.
1350 To parse a string $str as a number in some base $base use
1353 ($num, $n_unparsed) = POSIX::strtol($str, $base);
1355 The base should be zero or between 2 and 36, inclusive. When the base
1356 is zero or omitted strtol will use the string itself to determine the
1357 base: a leading "0x" or "0X" means hexadecimal; a leading "0" means
1358 octal; any other leading characters mean decimal. Thus, "1234" is
1359 parsed as a decimal number, "01234" as an octal number, and "0x1234"
1360 as a hexadecimal number.
1362 The second returned item and $! can be used to check for valid input:
1364 if (($str eq '') || ($n_unparsed != 0) || !$!) {
1365 die "Non-numeric input $str" . $! ? ": $!\n" : "\n";
1368 When called in a scalar context strtol returns the parsed number.
1372 String to unsigned (long) integer translation. strtoul() is identical
1373 to strtol() except that strtoul() only parses unsigned integers. See
1374 L</strtol> for details.
1376 Note: Some vendors supply strtod() and strtol() but not strtoul().
1377 Other vendors that do supply strtoul() parse "-1" as a valid value.
1381 String transformation. Returns the transformed string.
1383 $dst = POSIX::strxfrm( $src );
1385 Used in conjunction with the C<strcoll()> function, see L</strcoll>.
1387 Not really needed since Perl can do this transparently, see
1392 Retrieves values of system configurable variables.
1394 The following will get the machine's clock speed.
1396 $clock_ticks = POSIX::sysconf( &POSIX::_SC_CLK_TCK );
1398 Returns C<undef> on failure.
1402 This is identical to Perl's builtin C<system()> function, see
1407 This is identical to the C function C<tan()>, returning the
1408 tangent of the numerical argument. See also L<Math::Trig>.
1412 This is identical to the C function C<tanh()>, returning the
1413 hyperbolic tangent of the numerical argument. See also L<Math::Trig>.
1417 This is similar to the C function C<tcdrain()> for draining
1418 the output queue of its argument stream.
1420 Returns C<undef> on failure.
1424 This is similar to the C function C<tcflow()> for controlling
1425 the flow of its argument stream.
1427 Returns C<undef> on failure.
1431 This is similar to the C function C<tcflush()> for flushing
1432 the I/O buffers of its argument stream.
1434 Returns C<undef> on failure.
1438 This is identical to the C function C<tcgetpgrp()> for returning the
1439 process group identifier of the foreground process group of the controlling
1444 This is similar to the C function C<tcsendbreak()> for sending
1445 a break on its argument stream.
1447 Returns C<undef> on failure.
1451 This is similar to the C function C<tcsetpgrp()> for setting the
1452 process group identifier of the foreground process group of the controlling
1455 Returns C<undef> on failure.
1459 This is identical to Perl's builtin C<time()> function
1460 for returning the number of seconds since the epoch
1461 (whatever it is for the system), see L<perlfunc/time>.
1465 The times() function returns elapsed realtime since some point in the past
1466 (such as system startup), user and system times for this process, and user
1467 and system times used by child processes. All times are returned in clock
1470 ($realtime, $user, $system, $cuser, $csystem) = POSIX::times();
1472 Note: Perl's builtin C<times()> function returns four values, measured in
1477 Use method C<IO::File::new_tmpfile()> instead, or see L<File::Temp>.
1481 Returns a name for a temporary file.
1483 $tmpfile = POSIX::tmpnam();
1485 For security reasons, which are probably detailed in your system's
1486 documentation for the C library tmpnam() function, this interface
1487 should not be used; instead see L<File::Temp>.
1491 This is identical to the C function, except that it can apply to a single
1492 character or to a whole string. Consider using the C<lc()> function,
1493 see L<perlfunc/lc>, or the equivalent C<\L> operator inside doublequotish
1498 This is identical to the C function, except that it can apply to a single
1499 character or to a whole string. Consider using the C<uc()> function,
1500 see L<perlfunc/uc>, or the equivalent C<\U> operator inside doublequotish
1505 This is identical to the C function C<ttyname()> for returning the
1506 name of the current terminal.
1510 Retrieves the time conversion information from the C<tzname> variable.
1513 ($std, $dst) = POSIX::tzname();
1517 This is identical to the C function C<tzset()> for setting
1518 the current timezone based on the environment variable C<TZ>,
1519 to be used by C<ctime()>, C<localtime()>, C<mktime()>, and C<strftime()>
1524 This is identical to Perl's builtin C<umask()> function
1525 for setting (and querying) the file creation permission mask,
1526 see L<perlfunc/umask>.
1530 Get name of current operating system.
1532 ($sysname, $nodename, $release, $version, $machine) = POSIX::uname();
1534 Note that the actual meanings of the various fields are not
1535 that well standardized, do not expect any great portability.
1536 The C<$sysname> might be the name of the operating system,
1537 the C<$nodename> might be the name of the host, the C<$release>
1538 might be the (major) release number of the operating system,
1539 the C<$version> might be the (minor) release number of the
1540 operating system, and the C<$machine> might be a hardware identifier.
1545 Use method C<IO::Handle::ungetc()> instead.
1549 This is identical to Perl's builtin C<unlink()> function
1550 for removing files, see L<perlfunc/unlink>.
1554 This is identical to Perl's builtin C<utime()> function
1555 for changing the time stamps of files and directories,
1556 see L<perlfunc/utime>.
1560 vfprintf() is C-specific, see L<perlfunc/printf> instead.
1564 vprintf() is C-specific, see L<perlfunc/printf> instead.
1568 vsprintf() is C-specific, see L<perlfunc/sprintf> instead.
1572 This is identical to Perl's builtin C<wait()> function,
1573 see L<perlfunc/wait>.
1577 Wait for a child process to change state. This is identical to Perl's
1578 builtin C<waitpid()> function, see L<perlfunc/waitpid>.
1580 $pid = POSIX::waitpid( -1, POSIX::WNOHANG );
1581 print "status = ", ($? / 256), "\n";
1585 This is identical to the C function C<wcstombs()>.
1586 Perl does not have any support for the wide and multibyte
1587 characters of the C standards, so this might be a rather
1592 This is identical to the C function C<wctomb()>.
1593 Perl does not have any support for the wide and multibyte
1594 characters of the C standards, so this might be a rather
1599 Write to a file. This uses file descriptors such as those obtained by
1600 calling C<POSIX::open>.
1602 $fd = POSIX::open( "foo", &POSIX::O_WRONLY );
1604 $bytes = POSIX::write( $b, $buf, 5 );
1606 Returns C<undef> on failure.
1608 See also L<perlfunc/syswrite>.
1614 =head2 POSIX::SigAction
1620 Creates a new C<POSIX::SigAction> object which corresponds to the C
1621 C<struct sigaction>. This object will be destroyed automatically when it is
1622 no longer needed. The first parameter is the fully-qualified name of a sub
1623 which is a signal-handler. The second parameter is a C<POSIX::SigSet>
1624 object, it defaults to the empty set. The third parameter contains the
1625 C<sa_flags>, it defaults to 0.
1627 $sigset = POSIX::SigSet->new(SIGINT, SIGQUIT);
1628 $sigaction = POSIX::SigAction->new( 'main::handler', $sigset, &POSIX::SA_NOCLDSTOP );
1630 This C<POSIX::SigAction> object should be used with the C<POSIX::sigaction()>
1643 accessor functions to get/set the values of a SigAction object.
1645 $sigset = $sigaction->mask;
1646 $sigaction->flags(&POSIX::SA_RESTART);
1650 =head2 POSIX::SigSet
1656 Create a new SigSet object. This object will be destroyed automatically
1657 when it is no longer needed. Arguments may be supplied to initialize the
1660 Create an empty set.
1662 $sigset = POSIX::SigSet->new;
1664 Create a set with SIGUSR1.
1666 $sigset = POSIX::SigSet->new( &POSIX::SIGUSR1 );
1670 Add a signal to a SigSet object.
1672 $sigset->addset( &POSIX::SIGUSR2 );
1674 Returns C<undef> on failure.
1678 Remove a signal from the SigSet object.
1680 $sigset->delset( &POSIX::SIGUSR2 );
1682 Returns C<undef> on failure.
1686 Initialize the SigSet object to be empty.
1688 $sigset->emptyset();
1690 Returns C<undef> on failure.
1694 Initialize the SigSet object to include all signals.
1698 Returns C<undef> on failure.
1702 Tests the SigSet object to see if it contains a specific signal.
1704 if( $sigset->ismember( &POSIX::SIGUSR1 ) ){
1705 print "contains SIGUSR1\n";
1710 =head2 POSIX::Termios
1716 Create a new Termios object. This object will be destroyed automatically
1717 when it is no longer needed. A Termios object corresponds to the termios
1718 C struct. new() mallocs a new one, getattr() fills it from a file descriptor,
1719 and setattr() sets a file descriptor's parameters to match Termios' contents.
1721 $termios = POSIX::Termios->new;
1725 Get terminal control attributes.
1727 Obtain the attributes for stdin.
1731 Obtain the attributes for stdout.
1733 $termios->getattr( 1 )
1735 Returns C<undef> on failure.
1739 Retrieve a value from the c_cc field of a termios object. The c_cc field is
1740 an array so an index must be specified.
1742 $c_cc[1] = $termios->getcc(1);
1746 Retrieve the c_cflag field of a termios object.
1748 $c_cflag = $termios->getcflag;
1752 Retrieve the c_iflag field of a termios object.
1754 $c_iflag = $termios->getiflag;
1758 Retrieve the input baud rate.
1760 $ispeed = $termios->getispeed;
1764 Retrieve the c_lflag field of a termios object.
1766 $c_lflag = $termios->getlflag;
1770 Retrieve the c_oflag field of a termios object.
1772 $c_oflag = $termios->getoflag;
1776 Retrieve the output baud rate.
1778 $ospeed = $termios->getospeed;
1782 Set terminal control attributes.
1784 Set attributes immediately for stdout.
1786 $termios->setattr( 1, &POSIX::TCSANOW );
1788 Returns C<undef> on failure.
1792 Set a value in the c_cc field of a termios object. The c_cc field is an
1793 array so an index must be specified.
1795 $termios->setcc( &POSIX::VEOF, 1 );
1799 Set the c_cflag field of a termios object.
1801 $termios->setcflag( $c_cflag | &POSIX::CLOCAL );
1805 Set the c_iflag field of a termios object.
1807 $termios->setiflag( $c_iflag | &POSIX::BRKINT );
1811 Set the input baud rate.
1813 $termios->setispeed( &POSIX::B9600 );
1815 Returns C<undef> on failure.
1819 Set the c_lflag field of a termios object.
1821 $termios->setlflag( $c_lflag | &POSIX::ECHO );
1825 Set the c_oflag field of a termios object.
1827 $termios->setoflag( $c_oflag | &POSIX::OPOST );
1831 Set the output baud rate.
1833 $termios->setospeed( &POSIX::B9600 );
1835 Returns C<undef> on failure.
1837 =item Baud rate values
1839 B38400 B75 B200 B134 B300 B1800 B150 B0 B19200 B1200 B9600 B600 B4800 B50 B2400 B110
1841 =item Terminal interface values
1843 TCSADRAIN TCSANOW TCOON TCIOFLUSH TCOFLUSH TCION TCIFLUSH TCSAFLUSH TCIOFF TCOOFF
1845 =item c_cc field values
1847 VEOF VEOL VERASE VINTR VKILL VQUIT VSUSP VSTART VSTOP VMIN VTIME NCCS
1849 =item c_cflag field values
1851 CLOCAL CREAD CSIZE CS5 CS6 CS7 CS8 CSTOPB HUPCL PARENB PARODD
1853 =item c_iflag field values
1855 BRKINT ICRNL IGNBRK IGNCR IGNPAR INLCR INPCK ISTRIP IXOFF IXON PARMRK
1857 =item c_lflag field values
1859 ECHO ECHOE ECHOK ECHONL ICANON IEXTEN ISIG NOFLSH TOSTOP
1861 =item c_oflag field values
1867 =head1 PATHNAME CONSTANTS
1873 _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
1877 =head1 POSIX CONSTANTS
1883 _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
1887 =head1 SYSTEM CONFIGURATION
1893 _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
1903 E2BIG EACCES EADDRINUSE EADDRNOTAVAIL EAFNOSUPPORT EAGAIN EALREADY EBADF
1904 EBUSY ECHILD ECONNABORTED ECONNREFUSED ECONNRESET EDEADLK EDESTADDRREQ
1905 EDOM EDQUOT EEXIST EFAULT EFBIG EHOSTDOWN EHOSTUNREACH EINPROGRESS EINTR
1906 EINVAL EIO EISCONN EISDIR ELOOP EMFILE EMLINK EMSGSIZE ENAMETOOLONG
1907 ENETDOWN ENETRESET ENETUNREACH ENFILE ENOBUFS ENODEV ENOENT ENOEXEC
1908 ENOLCK ENOMEM ENOPROTOOPT ENOSPC ENOSYS ENOTBLK ENOTCONN ENOTDIR
1909 ENOTEMPTY ENOTSOCK ENOTTY ENXIO EOPNOTSUPP EPERM EPFNOSUPPORT EPIPE
1910 EPROCLIM EPROTONOSUPPORT EPROTOTYPE ERANGE EREMOTE ERESTART EROFS
1911 ESHUTDOWN ESOCKTNOSUPPORT ESPIPE ESRCH ESTALE ETIMEDOUT ETOOMANYREFS
1912 ETXTBSY EUSERS EWOULDBLOCK EXDEV
1922 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
1932 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
1942 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
1952 LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME
1972 SA_NOCLDSTOP SA_NOCLDWAIT SA_NODEFER SA_ONSTACK SA_RESETHAND SA_RESTART
1973 SA_SIGINFO SIGABRT SIGALRM SIGCHLD SIGCONT SIGFPE SIGHUP SIGILL SIGINT
1974 SIGKILL SIGPIPE SIGQUIT SIGSEGV SIGSTOP SIGTERM SIGTSTP SIGTTIN SIGTTOU
1975 SIGUSR1 SIGUSR2 SIG_BLOCK SIG_DFL SIG_ERR SIG_IGN SIG_SETMASK
1986 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
1990 S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISREG
2000 EXIT_FAILURE EXIT_SUCCESS MB_CUR_MAX RAND_MAX
2010 BUFSIZ EOF FILENAME_MAX L_ctermid L_cuserid L_tmpname TMP_MAX
2020 CLK_TCK CLOCKS_PER_SEC
2030 R_OK SEEK_CUR SEEK_END SEEK_SET STDIN_FILENO STDOUT_FILENO STDERR_FILENO W_OK X_OK
2046 Do not suspend the calling process until a child process
2047 changes state but instead return immediately.
2051 Catch stopped child processes.
2057 WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG WIFSTOPPED WSTOPSIG
2063 WIFEXITED($?) returns true if the child process exited normally
2064 (C<exit()> or by falling off the end of C<main()>)
2068 WEXITSTATUS($?) returns the normal exit status of the child process
2069 (only meaningful if WIFEXITED($?) is true)
2073 WIFSIGNALED($?) returns true if the child process terminated because
2078 WTERMSIG($?) returns the signal the child process terminated for
2079 (only meaningful if WIFSIGNALED($?) is true)
2083 WIFSTOPPED($?) returns true if the child process is currently stopped
2084 (can happen only if you specified the WUNTRACED flag to waitpid())
2088 WSTOPSIG($?) returns the signal the child process was stopped for
2089 (only meaningful if WIFSTOPPED($?) is true)