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
24 This document gives a condensed list of the features available in the POSIX
25 module. Consult your operating system's manpages for general information on
26 most features. Consult L<perlfunc> for functions which are noted as being
27 identical or almost identical to Perl's builtin functions.
29 The first section describes POSIX functions from the 1003.1 specification.
30 The second section describes some classes for signal objects, TTY objects,
31 and other miscellaneous objects. The remaining sections list various
32 constants and macros in an organization which roughly follows IEEE Std
37 I<Everything is exported by default> (with a handful of exceptions).
38 This is an unfortunate backwards compatibility feature and its use is
39 B<strongly L<discouraged|perlpolicy/discouraged>>.
40 You should either prevent the exporting (by saying S<C<use POSIX ();>>,
41 as usual) and then use fully qualified names (e.g. C<POSIX::SEEK_END>),
42 or give an explicit import list.
43 If you do neither and opt for the default (as in S<C<use POSIX;>>), you
44 will import I<hundreds and hundreds> of symbols into your namespace.
46 A few functions are not implemented because they are C specific. If you
47 attempt to call these, they will print a message telling you that they
48 aren't implemented, and suggest using the Perl equivalent, should one
49 exist. For example, trying to access the C<setjmp()> call will elicit the
50 message "C<setjmp() is C-specific: use eval {} instead>".
52 Furthermore, some evil vendors will claim 1003.1 compliance, but in fact
53 are not so: they will not pass the PCTS (POSIX Compliance Test Suites).
54 For example, one vendor may not define C<EDEADLK>, or the semantics of the
55 errno values set by C<open(2)> might not be quite right. Perl does not
56 attempt to verify POSIX compliance. That means you can currently
57 successfully say "use POSIX", and then later in your program you find
58 that your vendor has been lax and there's no usable C<ICANON> macro after
59 all. This could be construed to be a bug.
67 This is identical to the C function C<_exit()>. It exits the program
68 immediately which means among other things buffered I/O is B<not> flushed.
70 Note that when using threads and in Linux this is B<not> a good way to
71 exit a thread because in Linux processes and threads are kind of the
72 same thing (Note: while this is the situation in early 2003 there are
73 projects under way to have threads with more POSIXly semantics in Linux).
74 If you want not to return from a thread, detach the thread.
78 This is identical to the C function C<abort()>. It terminates the
79 process with a C<SIGABRT> signal unless caught by a signal handler or
80 if the handler does not return normally (it e.g. does a C<longjmp>).
84 This is identical to Perl's builtin C<abs()> function, returning the absolute
85 value of its numerical argument (except that C<POSIX::abs()> must be provided
86 an explicit value (rather than relying on an implicit C<$_>):
88 $absolute_value = POSIX::abs(42); # good
90 $absolute_value = POSIX::abs(); # throws exception
94 Determines the accessibility of a file.
96 if( POSIX::access( "/", &POSIX::R_OK ) ){
97 print "have read permission\n";
100 Returns C<undef> on failure. Note: do not use C<access()> for
101 security purposes. Between the C<access()> call and the operation
102 you are preparing for the permissions might change: a classic
107 This is identical to the C function C<acos()>, returning
108 the arcus cosine of its numerical argument. See also L<Math::Trig>.
112 This is identical to the C function C<acosh()>, returning the
113 hyperbolic arcus cosine of its numerical argument [C99]. See also
118 This is identical to Perl's builtin C<alarm()> function, either for arming or
119 disarming the C<SIGARLM> timer, except that C<POSIX::alarm()> must be provided
120 an explicit value (rather than relying on an implicit C<$_>):
122 POSIX::alarm(3) # good
124 POSIX::alarm() # throws exception
128 This is identical to the C function C<asctime()>. It returns
131 "Fri Jun 2 18:22:13 2000\n\0"
133 and it is called thusly
135 $asctime = asctime($sec, $min, $hour, $mday, $mon,
136 $year, $wday, $yday, $isdst);
138 The C<$mon> is zero-based: January equals C<0>. The C<$year> is
139 1900-based: 2001 equals C<101>. C<$wday> and C<$yday> default to zero
140 (and are usually ignored anyway), and C<$isdst> defaults to -1.
144 This is identical to the C function C<asin()>, returning
145 the arcus sine of its numerical argument. See also L<Math::Trig>.
149 This is identical to the C function C<asinh()>, returning the
150 hyperbolic arcus sine of its numerical argument [C99]. See also
155 Unimplemented, but you can use L<perlfunc/die> and the L<Carp> module
156 to achieve similar things.
160 This is identical to the C function C<atan()>, returning the
161 arcus tangent of its numerical argument. See also L<Math::Trig>.
165 This is identical to the C function C<atanh()>, returning the
166 hyperbolic arcus tangent of its numerical argument [C99]. See also
171 This is identical to Perl's builtin C<atan2()> function, returning
172 the arcus tangent defined by its two numerical arguments, the I<y>
173 coordinate and the I<x> coordinate. See also L<Math::Trig>.
177 Not implemented. C<atexit()> is C-specific: use C<END {}> instead, see L<perlmod>.
181 Not implemented. C<atof()> is C-specific. Perl converts strings to numbers transparently.
182 If you need to force a scalar to a number, add a zero to it.
186 Not implemented. C<atoi()> is C-specific. Perl converts strings to numbers transparently.
187 If you need to force a scalar to a number, add a zero to it.
188 If you need to have just the integer part, see L<perlfunc/int>.
192 Not implemented. C<atol()> is C-specific. Perl converts strings to numbers transparently.
193 If you need to force a scalar to a number, add a zero to it.
194 If you need to have just the integer part, see L<perlfunc/int>.
198 C<bsearch()> not supplied. For doing binary search on wordlists,
203 Not implemented. C<calloc()> is C-specific. Perl does memory management transparently.
211 This is identical to the C function C<ceil()>, returning the smallest
212 integer value greater than or equal to the given numerical argument.
216 This is identical to Perl's builtin C<chdir()> function, allowing one to
217 change the working (default) directory -- see L<perlfunc/chdir> -- with the
218 exception that C<POSIX::chdir()> must be provided an explicit value (rather
219 than relying on an implicit C<$_>):
221 $rv = POSIX::chdir('path/to/dir'); # good
223 $rv = POSIX::chdir(); # throws exception
227 This is identical to Perl's builtin C<chmod()> function, allowing
228 one to change file and directory permissions -- see L<perlfunc/chmod> -- with
229 the exception that C<POSIX::chmod()> can only change one file at a time
230 (rather than a list of files):
232 $c = chmod 0664, $file1, $file2; # good
234 $c = POSIX::chmod 0664, $file1; # throws exception
236 $c = POSIX::chmod 0664, $file1, $file2; # throws exception
240 This is identical to Perl's builtin C<chown()> function, allowing one
241 to change file and directory owners and groups, see L<perlfunc/chown>.
245 Not implemented. Use the method C<IO::Handle::clearerr()> instead, to reset the error
246 state (if any) and EOF state (if any) of the given stream.
250 This is identical to the C function C<clock()>, returning the
251 amount of spent processor time in microseconds.
255 Close the file. This uses file descriptors such as those obtained by calling
258 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
261 Returns C<undef> on failure.
263 See also L<perlfunc/close>.
267 This is identical to Perl's builtin C<closedir()> function for closing
268 a directory handle, see L<perlfunc/closedir>.
272 This is identical to Perl's builtin C<cos()> function, for returning
273 the cosine of its numerical argument, see L<perlfunc/cos>.
274 See also L<Math::Trig>.
278 This is identical to the C function C<cosh()>, for returning
279 the hyperbolic cosine of its numeric argument. See also L<Math::Trig>.
283 Returns C<x> but with the sign of C<y> [C99].
285 $x_with_sign_of_y = POSIX::copysign($x, $y);
287 See also L</signbit>.
291 Create a new file. This returns a file descriptor like the ones returned by
292 C<POSIX::open>. Use C<POSIX::close> to close the file.
294 $fd = POSIX::creat( "foo", 0611 );
297 See also L<perlfunc/sysopen> and its C<O_CREAT> flag.
301 Generates the path name for the controlling terminal.
303 $path = POSIX::ctermid();
307 This is identical to the C function C<ctime()> and equivalent
308 to C<asctime(localtime(...))>, see L</asctime> and L</localtime>.
312 Get the login name of the owner of the current process.
314 $name = POSIX::cuserid();
318 This is identical to the C function C<difftime()>, for returning
319 the time difference (in seconds) between two times (as returned
320 by C<time()>), see L</time>.
324 Not implemented. C<div()> is C-specific, use L<perlfunc/int> on the usual C</> division and
329 This is similar to the C function C<dup()>, for duplicating a file
332 This uses file descriptors such as those obtained by calling
335 Returns C<undef> on failure.
339 This is similar to the C function C<dup2()>, for duplicating a file
340 descriptor to an another known file descriptor.
342 This uses file descriptors such as those obtained by calling
345 Returns C<undef> on failure.
349 The error function [C99].
353 The complementary error function [C99].
357 Returns the value of errno.
359 $errno = POSIX::errno();
361 This identical to the numerical values of the C<$!>, see L<perlvar/$ERRNO>.
365 Not implemented. C<execl()> is C-specific, see L<perlfunc/exec>.
369 Not implemented. C<execle()> is C-specific, see L<perlfunc/exec>.
373 Not implemented. C<execlp()> is C-specific, see L<perlfunc/exec>.
377 Not implemented. C<execv()> is C-specific, see L<perlfunc/exec>.
381 Not implemented. C<execve()> is C-specific, see L<perlfunc/exec>.
385 Not implemented. C<execvp()> is C-specific, see L<perlfunc/exec>.
389 This is identical to Perl's builtin C<exit()> function for exiting the
390 program, see L<perlfunc/exit>.
394 This is identical to Perl's builtin C<exp()> function for
395 returning the exponent (I<e>-based) of the numerical argument,
400 Equivalent to C<exp(x) - 1>, but more precise for small argument values [C99].
406 This is identical to Perl's builtin C<abs()> function for returning
407 the absolute value of the numerical argument, see L<perlfunc/abs>.
411 Not implemented. Use method C<IO::Handle::close()> instead, or see L<perlfunc/close>.
415 This is identical to Perl's builtin C<fcntl()> function,
416 see L<perlfunc/fcntl>.
420 Not implemented. Use method C<IO::Handle::new_from_fd()> instead, or see L<perlfunc/open>.
424 Not implemented. Use method C<IO::Handle::eof()> instead, or see L<perlfunc/eof>.
428 Not implemented. Use method C<IO::Handle::error()> instead.
432 Not implemented. Use method C<IO::Handle::flush()> instead.
433 See also C<L<perlvar/$OUTPUT_AUTOFLUSH>>.
437 Not implemented. Use method C<IO::Handle::getc()> instead, or see L<perlfunc/read>.
441 Not implemented. Use method C<IO::Seekable::getpos()> instead, or see L<perlfunc/seek>.
445 Not implemented. Use method C<IO::Handle::gets()> instead. Similar to E<lt>E<gt>, also known
446 as L<perlfunc/readline>.
450 Not implemented. Use method C<IO::Handle::fileno()> instead, or see L<perlfunc/fileno>.
454 This is identical to the C function C<floor()>, returning the largest
455 integer value less than or equal to the numerical argument.
459 "Positive difference", S<C<x - y>> if S<C<x E<gt> y>>, zero otherwise [C99].
463 Returns the current floating point rounding mode, one of
465 FE_TONEAREST FE_TOWARDZERO FE_UPWARD FE_UPWARD
467 C<FE_TONEAREST> is like L</round>, C<FE_TOWARDZERO> is like L</trunc> [C99].
471 Sets the floating point rounding mode, see L</fegetround> [C99].
475 "Fused multiply-add", S<C<x * y + z>>, possibly faster (and less lossy)
476 than the explicit two operations [C99].
478 my $fused = POSIX::fma($x, $y, $z);
482 Maximum of C<x> and C<y>, except when either is C<NaN>, returns the other [C99].
484 my $min = POSIX::fmax($x, $y);
488 Minimum of C<x> and C<y>, except when either is C<NaN>, returns the other [C99].
490 my $min = POSIX::fmin($x, $y);
494 This is identical to the C function C<fmod()>.
498 It returns the remainder S<C<$r = $x - $n*$y>>, where S<C<$n = trunc($x/$y)>>.
499 The C<$r> has the same sign as C<$x> and magnitude (absolute value)
500 less than the magnitude of C<$y>.
504 Not implemented. Use method C<IO::File::open()> instead, or see L<perlfunc/open>.
508 This is identical to Perl's builtin C<fork()> function
509 for duplicating the current process, see L<perlfunc/fork>
510 and L<perlfork> if you are in Windows.
514 Retrieves the value of a configurable limit on a file or directory. This
515 uses file descriptors such as those obtained by calling C<POSIX::open>.
517 The following will determine the maximum length of the longest allowable
518 pathname on the filesystem which holds F</var/foo>.
520 $fd = POSIX::open( "/var/foo", &POSIX::O_RDONLY );
521 $path_max = POSIX::fpathconf($fd, &POSIX::_PC_PATH_MAX);
523 Returns C<undef> on failure.
529 FP_NORMAL FP_ZERO FP_SUBNORMAL FP_INFINITE FP_NAN
531 telling the class of the argument [C99]. C<FP_INFINITE> is positive
532 or negative infinity, C<FP_NAN> is not-a-number. C<FP_SUBNORMAL>
533 means subnormal numbers (also known as denormals), very small numbers
534 with low precision. C<FP_ZERO> is zero. C<FP_NORMAL> is all the rest.
538 Not implemented. C<fprintf()> is C-specific, see L<perlfunc/printf> instead.
542 Not implemented. C<fputc()> is C-specific, see L<perlfunc/print> instead.
546 Not implemented. C<fputs()> is C-specific, see L<perlfunc/print> instead.
550 Not implemented. C<fread()> is C-specific, see L<perlfunc/read> instead.
554 Not implemented. C<free()> is C-specific. Perl does memory management transparently.
558 Not implemented. C<freopen()> is C-specific, see L<perlfunc/open> instead.
562 Return the mantissa and exponent of a floating-point number.
564 ($mantissa, $exponent) = POSIX::frexp( 1.234e56 );
568 Not implemented. C<fscanf()> is C-specific, use E<lt>E<gt> and regular expressions instead.
572 Not implemented. Use method C<IO::Seekable::seek()> instead, or see L<perlfunc/seek>.
576 Not implemented. Use method C<IO::Seekable::setpos()> instead, or seek L<perlfunc/seek>.
580 Get file status. This uses file descriptors such as those obtained by
581 calling C<POSIX::open>. The data returned is identical to the data from
582 Perl's builtin C<stat> function.
584 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
585 @stats = POSIX::fstat( $fd );
589 Not implemented. Use method C<IO::Handle::sync()> instead.
593 Not implemented. Use method C<IO::Seekable::tell()> instead, or see L<perlfunc/tell>.
597 Not implemented. C<fwrite()> is C-specific, see L<perlfunc/print> instead.
601 This is identical to Perl's builtin C<getc()> function,
602 see L<perlfunc/getc>.
606 Returns one character from STDIN. Identical to Perl's C<getc()>,
607 see L<perlfunc/getc>.
611 Returns the name of the current working directory.
616 Returns the effective group identifier. Similar to Perl' s builtin
617 variable C<$(>, see L<perlvar/$EGID>.
621 Returns the value of the specified environment variable.
622 The same information is available through the C<%ENV> array.
626 Returns the effective user identifier. Identical to Perl's builtin C<$E<gt>>
627 variable, see L<perlvar/$EUID>.
631 Returns the user's real group identifier. Similar to Perl's builtin
632 variable C<$)>, see L<perlvar/$GID>.
636 This is identical to Perl's builtin C<getgrgid()> function for
637 returning group entries by group identifiers, see
638 L<perlfunc/getgrgid>.
642 This is identical to Perl's builtin C<getgrnam()> function for
643 returning group entries by group names, see L<perlfunc/getgrnam>.
647 Returns the ids of the user's supplementary groups. Similar to Perl's
648 builtin variable C<$)>, see L<perlvar/$GID>.
652 This is identical to Perl's builtin C<getlogin()> function for
653 returning the user name associated with the current session, see
654 L<perlfunc/getlogin>.
658 use POSIX ':nan_payload';
661 Returns the C<NaN> payload.
663 Note the API instability warning in L</setpayload>.
665 See L</nan> for more discussion about C<NaN>.
669 This is identical to Perl's builtin C<getpgrp()> function for
670 returning the process group identifier of the current process, see
675 Returns the process identifier. Identical to Perl's builtin
676 variable C<$$>, see L<perlvar/$PID>.
680 This is identical to Perl's builtin C<getppid()> function for
681 returning the process identifier of the parent process of the current
682 process , see L<perlfunc/getppid>.
686 This is identical to Perl's builtin C<getpwnam()> function for
687 returning user entries by user names, see L<perlfunc/getpwnam>.
691 This is identical to Perl's builtin C<getpwuid()> function for
692 returning user entries by user identifiers, see L<perlfunc/getpwuid>.
696 Returns one line from C<STDIN>, similar to E<lt>E<gt>, also known
697 as the C<readline()> function, see L<perlfunc/readline>.
699 B<NOTE>: if you have C programs that still use C<gets()>, be very
700 afraid. The C<gets()> function is a source of endless grief because
701 it has no buffer overrun checks. It should B<never> be used. The
702 C<fgets()> function should be preferred instead.
706 Returns the user's identifier. Identical to Perl's builtin C<$E<lt>> variable,
711 This is identical to Perl's builtin C<gmtime()> function for
712 converting seconds since the epoch to a date in Greenwich Mean Time,
713 see L<perlfunc/gmtime>.
717 Equivalent to C<S<sqrt(x * x + y * y)>> except more stable on very large
718 or very small arguments [C99].
722 Integer binary logarithm [C99]
724 For example C<ilogb(20)> is 4, as an integer.
730 The infinity as a constant:
733 my $pos_inf = +Inf; # Or just Inf.
736 See also L</isinf>, and L</fpclassify>.
740 This function has been removed as of v5.24. It was very similar to
741 matching against S<C<qr/ ^ [[:alnum:]]+ $ /x>>, which you should convert
742 to use instead. See L<perlrecharclass/POSIX Character Classes>.
746 This function has been removed as of v5.24. It was very similar to
747 matching against S<C<qr/ ^ [[:alpha:]]+ $ /x>>, which you should convert
748 to use instead. See L<perlrecharclass/POSIX Character Classes>.
752 Returns a boolean indicating whether the specified filehandle is connected
753 to a tty. Similar to the C<-t> operator, see L<perlfunc/-X>.
757 This function has been removed as of v5.24. It was very similar to
758 matching against S<C<qr/ ^ [[:cntrl:]]+ $ /x>>, which you should convert
759 to use instead. See L<perlrecharclass/POSIX Character Classes>.
763 This function has been removed as of v5.24. It was very similar to
764 matching against S<C<qr/ ^ [[:digit:]]+ $ /x>>, which you should convert
765 to use instead. See L<perlrecharclass/POSIX Character Classes>.
769 Returns true if the argument is a finite number (that is, not an
770 infinity, or the not-a-number) [C99].
772 See also L</isinf>, L</isnan>, and L</fpclassify>.
776 This function has been removed as of v5.24. It was very similar to
777 matching against S<C<qr/ ^ [[:graph:]]+ $ /x>>, which you should convert
778 to use instead. See L<perlrecharclass/POSIX Character Classes>.
782 (Also C<isgreaterequal>, C<isless>, C<islessequal>, C<islessgreater>,
785 Floating point comparisons which handle the C<NaN> [C99].
789 Returns true if the argument is an infinity (positive or negative) [C99].
791 See also L</Inf>, L</isnan>, L</isfinite>, and L</fpclassify>.
795 This function has been removed as of v5.24. It was very similar to
796 matching against S<C<qr/ ^ [[:lower:]]+ $ /x>>, which you should convert
797 to use instead. See L<perlrecharclass/POSIX Character Classes>.
801 Returns true if the argument is C<NaN> (not-a-number) [C99].
803 Note that you cannot test for "C<NaN>-ness" with
807 since the C<NaN> is not equivalent to anything, B<including itself>.
809 See also L</nan>, L</NaN>, L</isinf>, and L</fpclassify>.
813 Returns true if the argument is normal (that is, not a subnormal/denormal,
814 and not an infinity, or a not-a-number) [C99].
816 See also L</isfinite>, and L</fpclassify>.
820 This function has been removed as of v5.24. It was very similar to
821 matching against S<C<qr/ ^ [[:print:]]+ $ /x>>, which you should convert
822 to use instead. See L<perlrecharclass/POSIX Character Classes>.
826 This function has been removed as of v5.24. It was very similar to
827 matching against S<C<qr/ ^ [[:punct:]]+ $ /x>>, which you should convert
828 to use instead. See L<perlrecharclass/POSIX Character Classes>.
832 use POSIX ':nan_payload';
833 issignaling($var, $payload)
835 Return true if the argument is a I<signaling> NaN.
837 Note the API instability warning in L</setpayload>.
839 See L</nan> for more discussion about C<NaN>.
843 This function has been removed as of v5.24. It was very similar to
844 matching against S<C<qr/ ^ [[:space:]]+ $ /x>>, which you should convert
845 to use instead. See L<perlrecharclass/POSIX Character Classes>.
849 This function has been removed as of v5.24. It was very similar to
850 matching against S<C<qr/ ^ [[:upper:]]+ $ /x>>, which you should convert
851 to use instead. See L<perlrecharclass/POSIX Character Classes>.
855 This function has been removed as of v5.24. It was very similar to
856 matching against S<C<qr/ ^ [[:xdigit:]]+ $ /x>>, which you should
857 convert to use instead. See L<perlrecharclass/POSIX Character Classes>.
871 The Bessel function of the first kind of the order zero.
875 This is identical to Perl's builtin C<kill()> function for sending
876 signals to processes (often to terminate them), see L<perlfunc/kill>.
880 Not implemented. (For returning absolute values of long integers.)
881 C<labs()> is C-specific, see L<perlfunc/abs> instead.
885 This is identical to the C function, except the order of arguments is
886 consistent with Perl's builtin C<chown()> with the added restriction
887 of only one path, not a list of paths. Does the same thing as the
888 C<chown()> function but changes the owner of a symbolic link instead
889 of the file the symbolic link points to.
891 POSIX::lchown($uid, $gid, $file_path);
895 This is identical to the C function C<ldexp()>
896 for multiplying floating point numbers with powers of two.
898 $x_quadrupled = POSIX::ldexp($x, 2);
902 Not implemented. (For computing dividends of long integers.)
903 C<ldiv()> is C-specific, use C</> and C<int()> instead.
907 The logarithm of the Gamma function [C99].
913 Equivalent to S<C<log(1 + x)>>, but more stable results for small argument
918 Logarithm base two [C99].
924 Integer binary logarithm [C99].
926 For example C<logb(20)> is 4, as a floating point number.
932 This is identical to Perl's builtin C<link()> function
933 for creating hard links into files, see L<perlfunc/link>.
937 Get numeric formatting information. Returns a reference to a hash
938 containing the current underlying locale's formatting values. Users of this function
939 should also read L<perllocale>, which provides a comprehensive
940 discussion of Perl locale handling, including
941 L<a section devoted to this function|perllocale/The localeconv function>.
942 It should not be used in a threaded application unless it's certain that
943 the underlying locale is C or POSIX. This is because it otherwise
944 changes the locale, which globally affects all threads simultaneously.
946 Here is how to query the database for the B<de> (Deutsch or German) locale.
948 my $loc = POSIX::setlocale( &POSIX::LC_ALL, "de" );
949 print "Locale: \"$loc\"\n";
950 my $lconv = POSIX::localeconv();
951 foreach my $property (qw(
978 printf qq(%s: "%s",\n),
979 $property, $lconv->{$property};
982 The members whose names begin with C<int_p_> and C<int_n_> were added by
983 POSIX.1-2008 and are only available on systems that support them.
987 This is identical to Perl's builtin C<localtime()> function for
988 converting seconds since the epoch to a date see L<perlfunc/localtime> except
989 that C<POSIX::localtime()> must be provided an explicit value (rather than
990 relying on an implicit C<$_>):
992 @localtime = POSIX::localtime(time); # good
994 @localtime = localtime(); # good
996 @localtime = POSIX::localtime(); # throws exception
1000 This is identical to Perl's builtin C<log()> function,
1001 returning the natural (I<e>-based) logarithm of the numerical argument,
1002 see L<perlfunc/log>.
1006 This is identical to the C function C<log10()>,
1007 returning the 10-base logarithm of the numerical argument.
1010 sub log10 { log($_[0]) / log(10) }
1014 sub log10 { log($_[0]) / 2.30258509299405 }
1018 sub log10 { log($_[0]) * 0.434294481903252 }
1022 Not implemented. C<longjmp()> is C-specific: use L<perlfunc/die> instead.
1026 Move the file's read/write position. This uses file descriptors such as
1027 those obtained by calling C<POSIX::open>.
1029 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
1030 $off_t = POSIX::lseek( $fd, 0, &POSIX::SEEK_SET );
1032 Returns C<undef> on failure.
1036 Depending on the current floating point rounding mode, rounds the
1037 argument either toward nearest (like L</round>), toward zero (like
1038 L</trunc>), downward (toward negative infinity), or upward (toward
1039 positive infinity) [C99].
1041 For the rounding mode, see L</fegetround>.
1045 Like L</round>, but as integer, as opposed to floating point [C99].
1047 See also L</ceil>, L</floor>, L</trunc>.
1049 Owing to an oversight, this is not currently exported by default, or as part of
1050 the C<:math_h_c99> export tag; importing it must therefore be done by explicit
1055 Not implemented. C<malloc()> is C-specific. Perl does memory management transparently.
1059 This is identical to the C function C<mblen()>.
1061 Core Perl does not have any support for the wide and multibyte
1062 characters of the C standards, except under UTF-8 locales, so this might
1063 be a rather useless function.
1065 However, Perl supports Unicode, see L<perluniintro>.
1069 This is identical to the C function C<mbstowcs()>.
1075 This is identical to the C function C<mbtowc()>.
1081 Not implemented. C<memchr()> is C-specific, see L<perlfunc/index> instead.
1085 Not implemented. C<memcmp()> is C-specific, use C<eq> instead, see L<perlop>.
1089 Not implemented. C<memcpy()> is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>.
1093 Not implemented. C<memmove()> is C-specific, use C<=>, see L<perlop>, or see L<perlfunc/substr>.
1097 Not implemented. C<memset()> is C-specific, use C<x> instead, see L<perlop>.
1101 This is identical to Perl's builtin C<mkdir()> function
1102 for creating directories, see L<perlfunc/mkdir>.
1106 This is similar to the C function C<mkfifo()> for creating
1109 if (mkfifo($path, $mode)) { ....
1111 Returns C<undef> on failure. The C<$mode> is similar to the
1112 mode of C<mkdir()>, see L<perlfunc/mkdir>, though for C<mkfifo>
1113 you B<must> specify the C<$mode>.
1117 Convert date/time info to a calendar time.
1121 mktime(sec, min, hour, mday, mon, year, wday = 0,
1122 yday = 0, isdst = -1)
1124 The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero,
1125 I<i.e.>, January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
1126 year (C<year>) is given in years since 1900; I<i.e.>, the year 1995 is 95; the
1127 year 2001 is 101. Consult your system's C<mktime()> manpage for details
1128 about these and the other arguments.
1130 Calendar time for December 12, 1995, at 10:30 am.
1132 $time_t = POSIX::mktime( 0, 30, 10, 12, 11, 95 );
1133 print "Date = ", POSIX::ctime($time_t);
1135 Returns C<undef> on failure.
1139 Return the integral and fractional parts of a floating-point number.
1141 ($fractional, $integral) = POSIX::modf( 3.14 );
1147 The not-a-number as a constant:
1152 See also L</nan>, C</isnan>, and L</fpclassify>.
1158 Returns C<NaN>, not-a-number [C99].
1160 The returned NaN is always a I<quiet> NaN, as opposed to I<signaling>.
1162 With an argument, can be used to generate a NaN with I<payload>.
1163 The argument is first interpreted as a floating point number,
1164 but then any fractional parts are truncated (towards zero),
1165 and the value is interpreted as an unsigned integer.
1166 The bits of this integer are stored in the unused bits of the NaN.
1168 The result has a dual nature: it is a NaN, but it also carries
1169 the integer inside it. The integer can be retrieved with L</getpayload>.
1170 Note, though, that the payload is not propagated, not even on copies,
1171 and definitely not in arithmetic operations.
1173 How many bits fit in the NaN depends on what kind of floating points
1174 are being used, but on the most common platforms (64-bit IEEE 754,
1175 or the x86 80-bit long doubles) there are 51 and 61 bits available,
1176 respectively. (There would be 52 and 62, but the quiet/signaling
1177 bit of NaNs takes away one.) However, because of the floating-point-to-
1178 integer-and-back conversions, please test carefully whether you get back
1179 what you put in. If your integers are only 32 bits wide, you probably
1180 should not rely on more than 32 bits of payload.
1182 Whether a "signaling" NaN is in any way different from a "quiet" NaN,
1183 depends on the platform. Also note that the payload of the default
1184 NaN (no argument to nan()) is not necessarily zero, use C<setpayload>
1185 to explicitly set the payload. On some platforms like the 32-bit x86,
1186 (unless using the 80-bit long doubles) the signaling bit is not supported
1189 See also L</isnan>, L</NaN>, L</setpayload> and L</issignaling>.
1193 Returns the nearest integer to the argument, according to the current
1194 rounding mode (see L</fegetround>) [C99].
1198 Returns the next representable floating point number after C<x> in the
1199 direction of C<y> [C99].
1201 my $nextafter = POSIX::nextafter($x, $y);
1203 Like L</nexttoward>, but potentially less accurate.
1207 Returns the next representable floating point number after C<x> in the
1208 direction of C<y> [C99].
1210 my $nexttoward = POSIX::nexttoward($x, $y);
1212 Like L</nextafter>, but potentially more accurate.
1216 This is similar to the C function C<nice()>, for changing
1217 the scheduling preference of the current process. Positive
1218 arguments mean a more polite process, negative values a more
1219 needy process. Normal (non-root) user processes can only change towards
1222 Returns C<undef> on failure.
1226 Not implemented. C<offsetof()> is C-specific, you probably want to see L<perlfunc/pack> instead.
1230 Open a file for reading for writing. This returns file descriptors, not
1231 Perl filehandles. Use C<POSIX::close> to close the file.
1233 Open a file read-only with mode 0666.
1235 $fd = POSIX::open( "foo" );
1237 Open a file for read and write.
1239 $fd = POSIX::open( "foo", &POSIX::O_RDWR );
1241 Open a file for write, with truncation.
1244 "foo", &POSIX::O_WRONLY | &POSIX::O_TRUNC
1247 Create a new file with mode 0640. Set up the file for writing.
1250 "foo", &POSIX::O_CREAT | &POSIX::O_WRONLY, 0640
1253 Returns C<undef> on failure.
1255 See also L<perlfunc/sysopen>.
1259 Open a directory for reading.
1261 $dir = POSIX::opendir( "/var" );
1262 @files = POSIX::readdir( $dir );
1263 POSIX::closedir( $dir );
1265 Returns C<undef> on failure.
1269 Retrieves the value of a configurable limit on a file or directory.
1271 The following will determine the maximum length of the longest allowable
1272 pathname on the filesystem which holds C</var>.
1274 $path_max = POSIX::pathconf( "/var",
1275 &POSIX::_PC_PATH_MAX );
1277 Returns C<undef> on failure.
1281 This is similar to the C function C<pause()>, which suspends
1282 the execution of the current process until a signal is received.
1284 Returns C<undef> on failure.
1288 This is identical to the C function C<perror()>, which outputs to the
1289 standard error stream the specified message followed by C<": "> and the
1290 current error string. Use the C<warn()> function and the C<$!>
1291 variable instead, see L<perlfunc/warn> and L<perlvar/$ERRNO>.
1295 Create an interprocess channel. This returns file descriptors like those
1296 returned by C<POSIX::open>.
1298 my ($read, $write) = POSIX::pipe();
1299 POSIX::write( $write, "hello", 5 );
1300 POSIX::read( $read, $buf, 5 );
1302 See also L<perlfunc/pipe>.
1306 Computes C<$x> raised to the power C<$exponent>.
1308 $ret = POSIX::pow( $x, $exponent );
1310 You can also use the C<**> operator, see L<perlop>.
1314 Formats and prints the specified arguments to C<STDOUT>.
1315 See also L<perlfunc/printf>.
1319 Not implemented. C<putc()> is C-specific, see L<perlfunc/print> instead.
1323 Not implemented. C<putchar()> is C-specific, see L<perlfunc/print> instead.
1327 Not implemented. C<puts()> is C-specific, see L<perlfunc/print> instead.
1331 Not implemented. C<qsort()> is C-specific, see L<perlfunc/sort> instead.
1335 Sends the specified signal to the current process.
1336 See also L<perlfunc/kill> and the C<$$> in L<perlvar/$PID>.
1340 Not implemented. C<rand()> is non-portable, see L<perlfunc/rand> instead.
1344 Read from a file. This uses file descriptors such as those obtained by
1345 calling C<POSIX::open>. If the buffer C<$buf> is not large enough for the
1346 read then Perl will extend it to make room for the request.
1348 $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
1349 $bytes = POSIX::read( $fd, $buf, 3 );
1351 Returns C<undef> on failure.
1353 See also L<perlfunc/sysread>.
1357 This is identical to Perl's builtin C<readdir()> function
1358 for reading directory entries, see L<perlfunc/readdir>.
1362 Not implemented. C<realloc()> is C-specific. Perl does memory management transparently.
1366 Given C<x> and C<y>, returns the value S<C<x - n*y>>, where C<n> is the integer
1367 closest to C<x>/C<y>. [C99]
1369 my $remainder = POSIX::remainder($x, $y)
1371 See also L</remquo>.
1375 This is identical to Perl's builtin C<unlink()> function
1376 for removing files, see L<perlfunc/unlink>.
1380 Like L</remainder> but also returns the low-order bits of the quotient (n)
1383 (This is quite esoteric interface, mainly used to implement numerical
1388 This is identical to Perl's builtin C<rename()> function
1389 for renaming files, see L<perlfunc/rename>.
1393 Seeks to the beginning of the file.
1397 This is identical to Perl's builtin C<rewinddir()> function for
1398 rewinding directory entry streams, see L<perlfunc/rewinddir>.
1402 Identical to L</lrint>.
1406 This is identical to Perl's builtin C<rmdir()> function
1407 for removing (empty) directories, see L<perlfunc/rmdir>.
1411 Returns the integer (but still as floating point) nearest to the
1414 See also L</ceil>, L</floor>, L</lround>, L</modf>, and L</trunc>.
1418 Returns S<C<x * 2**y>> [C99].
1420 See also L</frexp> and L</ldexp>.
1424 Not implemented. C<scanf()> is C-specific, use E<lt>E<gt> and regular expressions instead,
1429 Sets the real group identifier and the effective group identifier for
1430 this process. Similar to assigning a value to the Perl's builtin
1431 C<$)> variable, see L<perlvar/$EGID>, except that the latter
1432 will change only the real user identifier, and that the setgid()
1433 uses only a single numeric argument, as opposed to a space-separated
1438 Not implemented. C<setjmp()> is C-specific: use C<eval {}> instead,
1439 see L<perlfunc/eval>.
1443 WARNING! Do NOT use this function in a L<thread|threads>. The locale
1444 will change in all other threads at the same time, and should your
1445 thread get paused by the operating system, and another started, that
1446 thread will not have the locale it is expecting. On some platforms,
1447 there can be a race leading to segfaults if two threads call this
1448 function nearly simultaneously.
1450 Modifies and queries the program's underlying locale. Users of this
1451 function should read L<perllocale>, whch provides a comprehensive
1452 discussion of Perl locale handling, knowledge of which is necessary to
1453 properly use this function. It contains
1454 L<a section devoted to this function|perllocale/The setlocale function>.
1455 The discussion here is merely a summary reference for C<setlocale()>.
1456 Note that Perl itself is almost entirely unaffected by the locale
1457 except within the scope of S<C<"use locale">>. (Exceptions are listed
1458 in L<perllocale/Not within the scope of "use locale">.)
1460 The following examples assume
1462 use POSIX qw(setlocale LC_ALL LC_CTYPE);
1466 The following will set the traditional UNIX system locale behavior
1467 (the second argument C<"C">).
1469 $loc = setlocale( LC_ALL, "C" );
1471 The following will query the current C<LC_CTYPE> category. (No second
1472 argument means 'query'.)
1474 $loc = setlocale( LC_CTYPE );
1476 The following will set the C<LC_CTYPE> behaviour according to the locale
1477 environment variables (the second argument C<"">).
1478 Please see your system's C<setlocale(3)> documentation for the locale
1479 environment variables' meaning or consult L<perllocale>.
1481 $loc = setlocale( LC_CTYPE, "" );
1483 The following will set the C<LC_COLLATE> behaviour to Argentinian
1484 Spanish. B<NOTE>: The naming and availability of locales depends on
1485 your operating system. Please consult L<perllocale> for how to find
1486 out which locales are available in your system.
1488 $loc = setlocale( LC_COLLATE, "es_AR.ISO8859-1" );
1492 use POSIX ':nan_payload';
1493 setpayload($var, $payload);
1495 Sets the C<NaN> payload of var.
1497 NOTE: the NaN payload APIs are based on the latest (as of June 2015)
1498 proposed ISO C interfaces, but they are not yet a standard. Things
1501 See L</nan> for more discussion about C<NaN>.
1503 See also L</setpayloadsig>, L</isnan>, L</getpayload>, and L</issignaling>.
1505 =item C<setpayloadsig>
1507 use POSIX ':nan_payload';
1508 setpayloadsig($var, $payload);
1510 Like L</setpayload> but also makes the NaN I<signaling>.
1512 Depending on the platform the NaN may or may not behave differently.
1514 Note the API instability warning in L</setpayload>.
1516 Note that because how the floating point formats work out, on the most
1517 common platforms signaling payload of zero is best avoided,
1518 since it might end up being identical to C<+Inf>.
1520 See also L</nan>, L</isnan>, L</getpayload>, and L</issignaling>.
1524 This is similar to the C function C<setpgid()> for
1525 setting the process group identifier of the current process.
1527 Returns C<undef> on failure.
1531 This is identical to the C function C<setsid()> for
1532 setting the session identifier of the current process.
1536 Sets the real user identifier and the effective user identifier for
1537 this process. Similar to assigning a value to the Perl's builtin
1538 C<$E<lt>> variable, see L<perlvar/$UID>, except that the latter
1539 will change only the real user identifier.
1543 Detailed signal management. This uses C<POSIX::SigAction> objects for
1544 the C<action> and C<oldaction> arguments (the oldaction can also be
1545 just a hash reference). Consult your system's C<sigaction> manpage
1546 for details, see also C<POSIX::SigRt>.
1550 sigaction(signal, action, oldaction = 0)
1552 Returns C<undef> on failure. The C<signal> must be a number (like
1553 C<SIGHUP>), not a string (like C<"SIGHUP">), though Perl does try hard
1556 If you use the C<SA_SIGINFO> flag, the signal handler will in addition to
1557 the first argument, the signal name, also receive a second argument, a
1558 hash reference, inside which are the following keys with the following
1559 semantics, as defined by POSIX/SUSv3:
1561 signo the signal number
1562 errno the error number
1563 code if this is zero or less, the signal was sent by
1564 a user process and the uid and pid make sense,
1565 otherwise the signal was sent by the kernel
1567 The constants for specific C<code> values can be imported individually
1568 or using the C<:signal_h_si_code> tag.
1570 The following are also defined by POSIX/SUSv3, but unfortunately
1571 not very widely implemented:
1573 pid the process id generating the signal
1574 uid the uid of the process id generating the signal
1575 status exit value or signal for SIGCHLD
1576 band band event for SIGPOLL
1577 addr address of faulting instruction or memory
1578 reference for SIGILL, SIGFPE, SIGSEGV or SIGBUS
1580 A third argument is also passed to the handler, which contains a copy
1581 of the raw binary contents of the C<siginfo> structure: if a system has
1582 some non-POSIX fields, this third argument is where to C<unpack()> them
1585 Note that not all C<siginfo> values make sense simultaneously (some are
1586 valid only for certain signals, for example), and not all values make
1587 sense from Perl perspective, you should to consult your system's
1588 C<sigaction> and possibly also C<siginfo> documentation.
1592 Not implemented. C<siglongjmp()> is C-specific: use L<perlfunc/die> instead.
1596 Returns zero for positive arguments, non-zero for negative arguments [C99].
1600 Examine signals that are blocked and pending. This uses C<POSIX::SigSet>
1601 objects for the C<sigset> argument. Consult your system's C<sigpending>
1602 manpage for details.
1608 Returns C<undef> on failure.
1610 =item C<sigprocmask>
1612 Change and/or examine calling process's signal mask. This uses
1613 C<POSIX::SigSet> objects for the C<sigset> and C<oldsigset> arguments.
1614 Consult your system's C<sigprocmask> manpage for details.
1618 sigprocmask(how, sigset, oldsigset = 0)
1620 Returns C<undef> on failure.
1622 Note that you can't reliably block or unblock a signal from its own signal
1623 handler if you're using safe signals. Other signals can be blocked or unblocked
1628 Not implemented. C<sigsetjmp()> is C-specific: use C<eval {}> instead,
1629 see L<perlfunc/eval>.
1633 Install a signal mask and suspend process until signal arrives. This uses
1634 C<POSIX::SigSet> objects for the C<signal_mask> argument. Consult your
1635 system's C<sigsuspend> manpage for details.
1639 sigsuspend(signal_mask)
1641 Returns C<undef> on failure.
1645 This is identical to Perl's builtin C<sin()> function
1646 for returning the sine of the numerical argument,
1647 see L<perlfunc/sin>. See also L<Math::Trig>.
1651 This is identical to the C function C<sinh()>
1652 for returning the hyperbolic sine of the numerical argument.
1653 See also L<Math::Trig>.
1657 This is functionally identical to Perl's builtin C<sleep()> function
1658 for suspending the execution of the current for process for certain
1659 number of seconds, see L<perlfunc/sleep>. There is one significant
1660 difference, however: C<POSIX::sleep()> returns the number of
1661 B<unslept> seconds, while the C<CORE::sleep()> returns the
1662 number of slept seconds.
1666 This is similar to Perl's builtin C<sprintf()> function
1667 for returning a string that has the arguments formatted as requested,
1668 see L<perlfunc/sprintf>.
1672 This is identical to Perl's builtin C<sqrt()> function.
1673 for returning the square root of the numerical argument,
1674 see L<perlfunc/sqrt>.
1678 Give a seed the pseudorandom number generator, see L<perlfunc/srand>.
1682 Not implemented. C<sscanf()> is C-specific, use regular expressions instead,
1687 This is identical to Perl's builtin C<stat()> function
1688 for returning information about files and directories.
1692 Not implemented. C<strcat()> is C-specific, use C<.=> instead, see L<perlop>.
1696 Not implemented. C<strchr()> is C-specific, see L<perlfunc/index> instead.
1700 Not implemented. C<strcmp()> is C-specific, use C<eq> or C<cmp> instead, see L<perlop>.
1704 This is identical to the C function C<strcoll()>
1705 for collating (comparing) strings transformed using
1706 the C<strxfrm()> function. Not really needed since
1707 Perl can do this transparently, see L<perllocale>.
1709 Beware that in a UTF-8 locale, anything you pass to this function must
1710 be in UTF-8; and when not in a UTF-8 locale, anything passed must not be
1715 Not implemented. C<strcpy()> is C-specific, use C<=> instead, see L<perlop>.
1719 Not implemented. C<strcspn()> is C-specific, use regular expressions instead,
1724 Returns the error string for the specified errno.
1725 Identical to the string form of C<$!>, see L<perlvar/$ERRNO>.
1729 Convert date and time information to string. Returns the string.
1733 strftime(fmt, sec, min, hour, mday, mon, year,
1734 wday = -1, yday = -1, isdst = -1)
1736 The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero,
1737 I<i.e.>, January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
1738 year (C<year>) is given in years since 1900, I<i.e.>, the year 1995 is 95; the
1739 year 2001 is 101. Consult your system's C<strftime()> manpage for details
1740 about these and the other arguments.
1742 If you want your code to be portable, your format (C<fmt>) argument
1743 should use only the conversion specifiers defined by the ANSI C
1744 standard (C89, to play safe). These are C<aAbBcdHIjmMpSUwWxXyYZ%>.
1745 But even then, the B<results> of some of the conversion specifiers are
1746 non-portable. For example, the specifiers C<aAbBcpZ> change according
1747 to the locale settings of the user, and both how to set locales (the
1748 locale names) and what output to expect are non-standard.
1749 The specifier C<c> changes according to the timezone settings of the
1750 user and the timezone computation rules of the operating system.
1751 The C<Z> specifier is notoriously unportable since the names of
1752 timezones are non-standard. Sticking to the numeric specifiers is the
1755 The given arguments are made consistent as though by calling
1756 C<mktime()> before calling your system's C<strftime()> function,
1757 except that the C<isdst> value is not affected.
1759 The string for Tuesday, December 12, 1995.
1761 $str = POSIX::strftime( "%A, %B %d, %Y",
1762 0, 0, 0, 12, 11, 95, 2 );
1767 Not implemented. C<strlen()> is C-specific, use C<length()> instead, see L<perlfunc/length>.
1771 Not implemented. C<strncat()> is C-specific, use C<.=> instead, see L<perlop>.
1775 Not implemented. C<strncmp()> is C-specific, use C<eq> instead, see L<perlop>.
1779 Not implemented. C<strncpy()> is C-specific, use C<=> instead, see L<perlop>.
1783 Not implemented. C<strpbrk()> is C-specific, use regular expressions instead,
1788 Not implemented. C<strrchr()> is C-specific, see L<perlfunc/rindex> instead.
1792 Not implemented. C<strspn()> is C-specific, use regular expressions instead,
1797 This is identical to Perl's builtin C<index()> function,
1798 see L<perlfunc/index>.
1802 String to double translation. Returns the parsed number and the number
1803 of characters in the unparsed portion of the string. Truly
1804 POSIX-compliant systems set C<$!> (C<$ERRNO>) to indicate a translation
1805 error, so clear C<$!> before calling C<strtod>. However, non-POSIX systems
1806 may not check for overflow, and therefore will never set C<$!>.
1808 C<strtod> respects any POSIX C<setlocale()> C<LC_TIME> settings,
1809 regardless of whether or not it is called from Perl code that is within
1810 the scope of S<C<use locale>>. This means it should not be used in a
1811 threaded application unless it's certain that the underlying locale is C
1812 or POSIX. This is because it otherwise changes the locale, which
1813 globally affects all threads simultaneously.
1815 To parse a string C<$str> as a floating point number use
1818 ($num, $n_unparsed) = POSIX::strtod($str);
1820 The second returned item and C<$!> can be used to check for valid input:
1822 if (($str eq '') || ($n_unparsed != 0) || $!) {
1823 die "Non-numeric input $str" . ($! ? ": $!\n" : "\n");
1826 When called in a scalar context C<strtod> returns the parsed number.
1830 Not implemented. C<strtok()> is C-specific, use regular expressions instead, see
1831 L<perlre>, or L<perlfunc/split>.
1835 String to (long) integer translation. Returns the parsed number and
1836 the number of characters in the unparsed portion of the string. Truly
1837 POSIX-compliant systems set C<$!> (C<$ERRNO>) to indicate a translation
1838 error, so clear C<$!> before calling C<strtol>. However, non-POSIX systems
1839 may not check for overflow, and therefore will never set C<$!>.
1841 C<strtol> should respect any POSIX I<setlocale()> settings.
1843 To parse a string C<$str> as a number in some base C<$base> use
1846 ($num, $n_unparsed) = POSIX::strtol($str, $base);
1848 The base should be zero or between 2 and 36, inclusive. When the base
1849 is zero or omitted C<strtol> will use the string itself to determine the
1850 base: a leading "0x" or "0X" means hexadecimal; a leading "0" means
1851 octal; any other leading characters mean decimal. Thus, "1234" is
1852 parsed as a decimal number, "01234" as an octal number, and "0x1234"
1853 as a hexadecimal number.
1855 The second returned item and C<$!> can be used to check for valid input:
1857 if (($str eq '') || ($n_unparsed != 0) || !$!) {
1858 die "Non-numeric input $str" . $! ? ": $!\n" : "\n";
1861 When called in a scalar context C<strtol> returns the parsed number.
1865 Like L</strtod> but for long doubles. Defined only if the
1866 system supports long doubles.
1870 String to unsigned (long) integer translation. C<strtoul()> is identical
1871 to C<strtol()> except that C<strtoul()> only parses unsigned integers. See
1872 L</strtol> for details.
1874 Note: Some vendors supply C<strtod()> and C<strtol()> but not C<strtoul()>.
1875 Other vendors that do supply C<strtoul()> parse "-1" as a valid value.
1879 String transformation. Returns the transformed string.
1881 $dst = POSIX::strxfrm( $src );
1883 Used in conjunction with the C<strcoll()> function, see L</strcoll>.
1885 Not really needed since Perl can do this transparently, see
1888 Beware that in a UTF-8 locale, anything you pass to this function must
1889 be in UTF-8; and when not in a UTF-8 locale, anything passed must not be
1894 Retrieves values of system configurable variables.
1896 The following will get the machine's clock speed.
1898 $clock_ticks = POSIX::sysconf( &POSIX::_SC_CLK_TCK );
1900 Returns C<undef> on failure.
1904 This is identical to Perl's builtin C<system()> function, see
1909 This is identical to the C function C<tan()>, returning the
1910 tangent of the numerical argument. See also L<Math::Trig>.
1914 This is identical to the C function C<tanh()>, returning the
1915 hyperbolic tangent of the numerical argument. See also L<Math::Trig>.
1919 This is similar to the C function C<tcdrain()> for draining
1920 the output queue of its argument stream.
1922 Returns C<undef> on failure.
1926 This is similar to the C function C<tcflow()> for controlling
1927 the flow of its argument stream.
1929 Returns C<undef> on failure.
1933 This is similar to the C function C<tcflush()> for flushing
1934 the I/O buffers of its argument stream.
1936 Returns C<undef> on failure.
1940 This is identical to the C function C<tcgetpgrp()> for returning the
1941 process group identifier of the foreground process group of the controlling
1944 =item C<tcsendbreak>
1946 This is similar to the C function C<tcsendbreak()> for sending
1947 a break on its argument stream.
1949 Returns C<undef> on failure.
1953 This is similar to the C function C<tcsetpgrp()> for setting the
1954 process group identifier of the foreground process group of the controlling
1957 Returns C<undef> on failure.
1961 The Gamma function [C99].
1963 See also L</lgamma>.
1967 This is identical to Perl's builtin C<time()> function
1968 for returning the number of seconds since the epoch
1969 (whatever it is for the system), see L<perlfunc/time>.
1973 The C<times()> function returns elapsed realtime since some point in the past
1974 (such as system startup), user and system times for this process, and user
1975 and system times used by child processes. All times are returned in clock
1978 ($realtime, $user, $system, $cuser, $csystem)
1981 Note: Perl's builtin C<times()> function returns four values, measured in
1986 Not implemented. Use method C<IO::File::new_tmpfile()> instead, or see L<File::Temp>.
1990 For security reasons, which are probably detailed in your system's
1991 documentation for the C library C<tmpnam()> function, this interface
1992 is no longer available; instead use L<File::Temp>.
1996 This is identical to the C function, except that it can apply to a single
1997 character or to a whole string, and currently operates as if the locale
1998 always is "C". Consider using the C<lc()> function, see L<perlfunc/lc>,
1999 see L<perlfunc/lc>, or the equivalent C<\L> operator inside doublequotish
2004 This is similar to the C function, except that it can apply to a single
2005 character or to a whole string, and currently operates as if the locale
2006 always is "C". Consider using the C<uc()> function, see L<perlfunc/uc>,
2007 or the equivalent C<\U> operator inside doublequotish strings.
2011 Returns the integer toward zero from the argument [C99].
2013 See also L</ceil>, L</floor>, and L</round>.
2017 This is identical to the C function C<ttyname()> for returning the
2018 name of the current terminal.
2022 Retrieves the time conversion information from the C<tzname> variable.
2025 ($std, $dst) = POSIX::tzname();
2029 This is identical to the C function C<tzset()> for setting
2030 the current timezone based on the environment variable C<TZ>,
2031 to be used by C<ctime()>, C<localtime()>, C<mktime()>, and C<strftime()>
2036 This is identical to Perl's builtin C<umask()> function
2037 for setting (and querying) the file creation permission mask,
2038 see L<perlfunc/umask>.
2042 Get name of current operating system.
2044 ($sysname, $nodename, $release, $version, $machine)
2047 Note that the actual meanings of the various fields are not
2048 that well standardized, do not expect any great portability.
2049 The C<$sysname> might be the name of the operating system,
2050 the C<$nodename> might be the name of the host, the C<$release>
2051 might be the (major) release number of the operating system,
2052 the C<$version> might be the (minor) release number of the
2053 operating system, and the C<$machine> might be a hardware identifier.
2058 Not implemented. Use method C<IO::Handle::ungetc()> instead.
2062 This is identical to Perl's builtin C<unlink()> function
2063 for removing files, see L<perlfunc/unlink>.
2067 This is identical to Perl's builtin C<utime()> function
2068 for changing the time stamps of files and directories,
2069 see L<perlfunc/utime>.
2073 Not implemented. C<vfprintf()> is C-specific, see L<perlfunc/printf> instead.
2077 Not implemented. C<vprintf()> is C-specific, see L<perlfunc/printf> instead.
2081 Not implemented. C<vsprintf()> is C-specific, see L<perlfunc/sprintf> instead.
2085 This is identical to Perl's builtin C<wait()> function,
2086 see L<perlfunc/wait>.
2090 Wait for a child process to change state. This is identical to Perl's
2091 builtin C<waitpid()> function, see L<perlfunc/waitpid>.
2093 $pid = POSIX::waitpid( -1, POSIX::WNOHANG );
2094 print "status = ", ($? / 256), "\n";
2098 This is identical to the C function C<wcstombs()>.
2104 This is identical to the C function C<wctomb()>.
2110 Write to a file. This uses file descriptors such as those obtained by
2111 calling C<POSIX::open>.
2113 $fd = POSIX::open( "foo", &POSIX::O_WRONLY );
2115 $bytes = POSIX::write( $fd, $buf, 5 );
2117 Returns C<undef> on failure.
2119 See also L<perlfunc/syswrite>.
2125 =head2 C<POSIX::SigAction>
2131 Creates a new C<POSIX::SigAction> object which corresponds to the C
2132 C<struct sigaction>. This object will be destroyed automatically when
2133 it is no longer needed. The first parameter is the handler, a sub
2134 reference. The second parameter is a C<POSIX::SigSet> object, it
2135 defaults to the empty set. The third parameter contains the
2136 C<sa_flags>, it defaults to 0.
2138 $sigset = POSIX::SigSet->new(SIGINT, SIGQUIT);
2139 $sigaction = POSIX::SigAction->new(
2140 \&handler, $sigset, &POSIX::SA_NOCLDSTOP
2143 This C<POSIX::SigAction> object is intended for use with the C<POSIX::sigaction()>
2156 accessor functions to get/set the values of a SigAction object.
2158 $sigset = $sigaction->mask;
2159 $sigaction->flags(&POSIX::SA_RESTART);
2163 accessor function for the "safe signals" flag of a SigAction object; see
2164 L<perlipc> for general information on safe (a.k.a. "deferred") signals. If
2165 you wish to handle a signal safely, use this accessor to set the "safe" flag
2166 in the C<POSIX::SigAction> object:
2168 $sigaction->safe(1);
2170 You may also examine the "safe" flag on the output action object which is
2171 filled in when given as the third parameter to C<POSIX::sigaction()>:
2173 sigaction(SIGINT, $new_action, $old_action);
2174 if ($old_action->safe) {
2175 # previous SIGINT handler used safe signals
2180 =head2 C<POSIX::SigRt>
2186 A hash of the POSIX realtime signal handlers. It is an extension of
2187 the standard C<%SIG>, the C<$POSIX::SIGRT{SIGRTMIN}> is roughly equivalent
2188 to C<$SIG{SIGRTMIN}>, but the right POSIX moves (see below) are made with
2189 the C<POSIX::SigSet> and C<POSIX::sigaction> instead of accessing the C<%SIG>.
2191 You can set the C<%POSIX::SIGRT> elements to set the POSIX realtime
2192 signal handlers, use C<delete> and C<exists> on the elements, and use
2193 C<scalar> on the C<%POSIX::SIGRT> to find out how many POSIX realtime
2194 signals there are available S<C<(SIGRTMAX - SIGRTMIN + 1>>, the C<SIGRTMAX> is
2195 a valid POSIX realtime signal).
2197 Setting the C<%SIGRT> elements is equivalent to calling this:
2200 my ($rtsig, $handler, $flags) = @_;
2201 my $sigset = POSIX::SigSet($rtsig);
2202 my $sigact = POSIX::SigAction->new($handler,$sigset,$flags);
2203 sigaction($rtsig, $sigact);
2206 The flags default to zero, if you want something different you can
2207 either use C<local> on C<$POSIX::SigRt::SIGACTION_FLAGS>, or you can
2208 derive from POSIX::SigRt and define your own C<new()> (the tied hash
2209 STORE method of the C<%SIGRT> calls C<new($rtsig, $handler, $SIGACTION_FLAGS)>,
2210 where the C<$rtsig> ranges from zero to S<C<SIGRTMAX - SIGRTMIN + 1)>>.
2212 Just as with any signal, you can use C<sigaction($rtsig, undef, $oa)> to
2213 retrieve the installed signal handler (or, rather, the signal action).
2215 B<NOTE:> whether POSIX realtime signals really work in your system, or
2216 whether Perl has been compiled so that it works with them, is outside
2221 Return the minimum POSIX realtime signal number available, or C<undef>
2222 if no POSIX realtime signals are available.
2226 Return the maximum POSIX realtime signal number available, or C<undef>
2227 if no POSIX realtime signals are available.
2231 =head2 C<POSIX::SigSet>
2237 Create a new SigSet object. This object will be destroyed automatically
2238 when it is no longer needed. Arguments may be supplied to initialize the
2241 Create an empty set.
2243 $sigset = POSIX::SigSet->new;
2245 Create a set with C<SIGUSR1>.
2247 $sigset = POSIX::SigSet->new( &POSIX::SIGUSR1 );
2251 Add a signal to a SigSet object.
2253 $sigset->addset( &POSIX::SIGUSR2 );
2255 Returns C<undef> on failure.
2259 Remove a signal from the SigSet object.
2261 $sigset->delset( &POSIX::SIGUSR2 );
2263 Returns C<undef> on failure.
2267 Initialize the SigSet object to be empty.
2269 $sigset->emptyset();
2271 Returns C<undef> on failure.
2275 Initialize the SigSet object to include all signals.
2279 Returns C<undef> on failure.
2283 Tests the SigSet object to see if it contains a specific signal.
2285 if( $sigset->ismember( &POSIX::SIGUSR1 ) ){
2286 print "contains SIGUSR1\n";
2291 =head2 C<POSIX::Termios>
2297 Create a new Termios object. This object will be destroyed automatically
2298 when it is no longer needed. A Termios object corresponds to the C<termios>
2299 C struct. C<new()> mallocs a new one, C<getattr()> fills it from a file descriptor,
2300 and C<setattr()> sets a file descriptor's parameters to match Termios' contents.
2302 $termios = POSIX::Termios->new;
2306 Get terminal control attributes.
2308 Obtain the attributes for C<stdin>.
2310 $termios->getattr( 0 ) # Recommended for clarity.
2313 Obtain the attributes for stdout.
2315 $termios->getattr( 1 )
2317 Returns C<undef> on failure.
2321 Retrieve a value from the C<c_cc> field of a C<termios> object. The C<c_cc> field is
2322 an array so an index must be specified.
2324 $c_cc[1] = $termios->getcc(1);
2328 Retrieve the C<c_cflag> field of a C<termios> object.
2330 $c_cflag = $termios->getcflag;
2334 Retrieve the C<c_iflag> field of a C<termios> object.
2336 $c_iflag = $termios->getiflag;
2340 Retrieve the input baud rate.
2342 $ispeed = $termios->getispeed;
2346 Retrieve the C<c_lflag> field of a C<termios> object.
2348 $c_lflag = $termios->getlflag;
2352 Retrieve the C<c_oflag> field of a C<termios> object.
2354 $c_oflag = $termios->getoflag;
2358 Retrieve the output baud rate.
2360 $ospeed = $termios->getospeed;
2364 Set terminal control attributes.
2366 Set attributes immediately for stdout.
2368 $termios->setattr( 1, &POSIX::TCSANOW );
2370 Returns C<undef> on failure.
2374 Set a value in the C<c_cc> field of a C<termios> object. The C<c_cc> field is an
2375 array so an index must be specified.
2377 $termios->setcc( &POSIX::VEOF, 1 );
2381 Set the C<c_cflag> field of a C<termios> object.
2383 $termios->setcflag( $c_cflag | &POSIX::CLOCAL );
2387 Set the C<c_iflag> field of a C<termios> object.
2389 $termios->setiflag( $c_iflag | &POSIX::BRKINT );
2393 Set the input baud rate.
2395 $termios->setispeed( &POSIX::B9600 );
2397 Returns C<undef> on failure.
2401 Set the C<c_lflag> field of a C<termios> object.
2403 $termios->setlflag( $c_lflag | &POSIX::ECHO );
2407 Set the C<c_oflag> field of a C<termios> object.
2409 $termios->setoflag( $c_oflag | &POSIX::OPOST );
2413 Set the output baud rate.
2415 $termios->setospeed( &POSIX::B9600 );
2417 Returns C<undef> on failure.
2419 =item Baud rate values
2421 C<B38400> C<B75> C<B200> C<B134> C<B300> C<B1800> C<B150> C<B0> C<B19200> C<B1200> C<B9600> C<B600> C<B4800> C<B50> C<B2400> C<B110>
2423 =item Terminal interface values
2425 C<TCSADRAIN> C<TCSANOW> C<TCOON> C<TCIOFLUSH> C<TCOFLUSH> C<TCION> C<TCIFLUSH> C<TCSAFLUSH> C<TCIOFF> C<TCOOFF>
2427 =item C<c_cc> field values
2429 C<VEOF> C<VEOL> C<VERASE> C<VINTR> C<VKILL> C<VQUIT> C<VSUSP> C<VSTART> C<VSTOP> C<VMIN> C<VTIME> C<NCCS>
2431 =item C<c_cflag> field values
2433 C<CLOCAL> C<CREAD> C<CSIZE> C<CS5> C<CS6> C<CS7> C<CS8> C<CSTOPB> C<HUPCL> C<PARENB> C<PARODD>
2435 =item C<c_iflag> field values
2437 C<BRKINT> C<ICRNL> C<IGNBRK> C<IGNCR> C<IGNPAR> C<INLCR> C<INPCK> C<ISTRIP> C<IXOFF> C<IXON> C<PARMRK>
2439 =item C<c_lflag> field values
2441 C<ECHO> C<ECHOE> C<ECHOK> C<ECHONL> C<ICANON> C<IEXTEN> C<ISIG> C<NOFLSH> C<TOSTOP>
2443 =item C<c_oflag> field values
2449 =head1 PATHNAME CONSTANTS
2455 C<_PC_CHOWN_RESTRICTED> C<_PC_LINK_MAX> C<_PC_MAX_CANON> C<_PC_MAX_INPUT> C<_PC_NAME_MAX>
2456 C<_PC_NO_TRUNC> C<_PC_PATH_MAX> C<_PC_PIPE_BUF> C<_PC_VDISABLE>
2460 =head1 POSIX CONSTANTS
2466 C<_POSIX_ARG_MAX> C<_POSIX_CHILD_MAX> C<_POSIX_CHOWN_RESTRICTED> C<_POSIX_JOB_CONTROL>
2467 C<_POSIX_LINK_MAX> C<_POSIX_MAX_CANON> C<_POSIX_MAX_INPUT> C<_POSIX_NAME_MAX>
2468 C<_POSIX_NGROUPS_MAX> C<_POSIX_NO_TRUNC> C<_POSIX_OPEN_MAX> C<_POSIX_PATH_MAX>
2469 C<_POSIX_PIPE_BUF> C<_POSIX_SAVED_IDS> C<_POSIX_SSIZE_MAX> C<_POSIX_STREAM_MAX>
2470 C<_POSIX_TZNAME_MAX> C<_POSIX_VDISABLE> C<_POSIX_VERSION>
2474 =head1 RESOURCE CONSTANTS
2476 Imported with the C<:sys_resource_h> tag.
2482 C<PRIO_PROCESS> C<PRIO_PGRP> C<PRIO_USER>
2486 =head1 SYSTEM CONFIGURATION
2492 C<_SC_ARG_MAX> C<_SC_CHILD_MAX> C<_SC_CLK_TCK> C<_SC_JOB_CONTROL> C<_SC_NGROUPS_MAX>
2493 C<_SC_OPEN_MAX> C<_SC_PAGESIZE> C<_SC_SAVED_IDS> C<_SC_STREAM_MAX> C<_SC_TZNAME_MAX>
2504 C<E2BIG> C<EACCES> C<EADDRINUSE> C<EADDRNOTAVAIL> C<EAFNOSUPPORT> C<EAGAIN> C<EALREADY> C<EBADF> C<EBADMSG>
2505 C<EBUSY> C<ECANCELED> C<ECHILD> C<ECONNABORTED> C<ECONNREFUSED> C<ECONNRESET> C<EDEADLK> C<EDESTADDRREQ>
2506 C<EDOM> C<EDQUOT> C<EEXIST> C<EFAULT> C<EFBIG> C<EHOSTDOWN> C<EHOSTUNREACH> C<EIDRM> C<EILSEQ> C<EINPROGRESS>
2507 C<EINTR> C<EINVAL> C<EIO> C<EISCONN> C<EISDIR> C<ELOOP> C<EMFILE> C<EMLINK> C<EMSGSIZE> C<ENAMETOOLONG>
2508 C<ENETDOWN> C<ENETRESET> C<ENETUNREACH> C<ENFILE> C<ENOBUFS> C<ENODATA> C<ENODEV> C<ENOENT> C<ENOEXEC>
2509 C<ENOLCK> C<ENOLINK> C<ENOMEM> C<ENOMSG> C<ENOPROTOOPT> C<ENOSPC> C<ENOSR> C<ENOSTR> C<ENOSYS> C<ENOTBLK>
2510 C<ENOTCONN> C<ENOTDIR> C<ENOTEMPTY> C<ENOTRECOVERABLE> C<ENOTSOCK> C<ENOTSUP> C<ENOTTY> C<ENXIO>
2511 C<EOPNOTSUPP> C<EOTHER> C<EOVERFLOW> C<EOWNERDEAD> C<EPERM> C<EPFNOSUPPORT> C<EPIPE> C<EPROCLIM> C<EPROTO>
2512 C<EPROTONOSUPPORT> C<EPROTOTYPE> C<ERANGE> C<EREMOTE> C<ERESTART> C<EROFS> C<ESHUTDOWN>
2513 C<ESOCKTNOSUPPORT> C<ESPIPE> C<ESRCH> C<ESTALE> C<ETIME> C<ETIMEDOUT> C<ETOOMANYREFS> C<ETXTBSY> C<EUSERS>
2514 C<EWOULDBLOCK> C<EXDEV>
2524 C<FD_CLOEXEC> C<F_DUPFD> C<F_GETFD> C<F_GETFL> C<F_GETLK> C<F_OK> C<F_RDLCK> C<F_SETFD> C<F_SETFL> C<F_SETLK>
2525 C<F_SETLKW> C<F_UNLCK> C<F_WRLCK> C<O_ACCMODE> C<O_APPEND> C<O_CREAT> C<O_EXCL> C<O_NOCTTY> C<O_NONBLOCK>
2526 C<O_RDONLY> C<O_RDWR> C<O_TRUNC> C<O_WRONLY>
2536 C<DBL_DIG> C<DBL_EPSILON> C<DBL_MANT_DIG> C<DBL_MAX> C<DBL_MAX_10_EXP> C<DBL_MAX_EXP> C<DBL_MIN>
2537 C<DBL_MIN_10_EXP> C<DBL_MIN_EXP> C<FLT_DIG> C<FLT_EPSILON> C<FLT_MANT_DIG> C<FLT_MAX>
2538 C<FLT_MAX_10_EXP> C<FLT_MAX_EXP> C<FLT_MIN> C<FLT_MIN_10_EXP> C<FLT_MIN_EXP> C<FLT_RADIX>
2539 C<FLT_ROUNDS> C<LDBL_DIG> C<LDBL_EPSILON> C<LDBL_MANT_DIG> C<LDBL_MAX> C<LDBL_MAX_10_EXP>
2540 C<LDBL_MAX_EXP> C<LDBL_MIN> C<LDBL_MIN_10_EXP> C<LDBL_MIN_EXP>
2544 =head1 FLOATING-POINT ENVIRONMENT
2550 C<FE_DOWNWARD> C<FE_TONEAREST> C<FE_TOWARDZERO> C<FE_UPWARD>
2551 on systems that support them.
2561 C<ARG_MAX> C<CHAR_BIT> C<CHAR_MAX> C<CHAR_MIN> C<CHILD_MAX> C<INT_MAX> C<INT_MIN> C<LINK_MAX> C<LONG_MAX>
2562 C<LONG_MIN> C<MAX_CANON> C<MAX_INPUT> C<MB_LEN_MAX> C<NAME_MAX> C<NGROUPS_MAX> C<OPEN_MAX> C<PATH_MAX>
2563 C<PIPE_BUF> C<SCHAR_MAX> C<SCHAR_MIN> C<SHRT_MAX> C<SHRT_MIN> C<SSIZE_MAX> C<STREAM_MAX> C<TZNAME_MAX>
2564 C<UCHAR_MAX> C<UINT_MAX> C<ULONG_MAX> C<USHRT_MAX>
2574 C<LC_ALL> C<LC_COLLATE> C<LC_CTYPE> C<LC_MONETARY> C<LC_NUMERIC> C<LC_TIME> C<LC_MESSAGES>
2575 on systems that support them.
2587 C<FP_ILOGB0> C<FP_ILOGBNAN> C<FP_INFINITE> C<FP_NAN> C<FP_NORMAL> C<FP_SUBNORMAL> C<FP_ZERO>
2588 C<INFINITY> C<NAN> C<Inf> C<NaN>
2589 C<M_1_PI> C<M_2_PI> C<M_2_SQRTPI> C<M_E> C<M_LN10> C<M_LN2> C<M_LOG10E> C<M_LOG2E> C<M_PI>
2590 C<M_PI_2> C<M_PI_4> C<M_SQRT1_2> C<M_SQRT2>
2591 on systems with C99 support.
2601 C<SA_NOCLDSTOP> C<SA_NOCLDWAIT> C<SA_NODEFER> C<SA_ONSTACK> C<SA_RESETHAND> C<SA_RESTART>
2602 C<SA_SIGINFO> C<SIGABRT> C<SIGALRM> C<SIGCHLD> C<SIGCONT> C<SIGFPE> C<SIGHUP> C<SIGILL> C<SIGINT>
2603 C<SIGKILL> C<SIGPIPE> C<SIGQUIT> C<SIGSEGV> C<SIGSTOP> C<SIGTERM> C<SIGTSTP> C<SIGTTIN> C<SIGTTOU>
2604 C<SIGUSR1> C<SIGUSR2> C<SIG_BLOCK> C<SIG_DFL> C<SIG_ERR> C<SIG_IGN> C<SIG_SETMASK>
2606 C<ILL_ILLOPC> C<ILL_ILLOPN> C<ILL_ILLADR> C<ILL_ILLTRP> C<ILL_PRVOPC> C<ILL_PRVREG> C<ILL_COPROC>
2607 C<ILL_BADSTK> C<FPE_INTDIV> C<FPE_INTOVF> C<FPE_FLTDIV> C<FPE_FLTOVF> C<FPE_FLTUND> C<FPE_FLTRES>
2608 C<FPE_FLTINV> C<FPE_FLTSUB> C<SEGV_MAPERR> C<SEGV_ACCERR> C<BUS_ADRALN> C<BUS_ADRERR>
2609 C<BUS_OBJERR> C<TRAP_BRKPT> C<TRAP_TRACE> C<CLD_EXITED> C<CLD_KILLED> C<CLD_DUMPED> C<CLD_TRAPPED>
2610 C<CLD_STOPPED> C<CLD_CONTINUED> C<POLL_IN> C<POLL_OUT> C<POLL_MSG> C<POLL_ERR> C<POLL_PRI>
2611 C<POLL_HUP> C<SI_USER> C<SI_QUEUE> C<SI_TIMER> C<SI_ASYNCIO> C<SI_MESGQ>
2621 C<S_IRGRP> C<S_IROTH> C<S_IRUSR> C<S_IRWXG> C<S_IRWXO> C<S_IRWXU> C<S_ISGID> C<S_ISUID> C<S_IWGRP> C<S_IWOTH>
2622 C<S_IWUSR> C<S_IXGRP> C<S_IXOTH> C<S_IXUSR>
2626 C<S_ISBLK> C<S_ISCHR> C<S_ISDIR> C<S_ISFIFO> C<S_ISREG>
2636 C<EXIT_FAILURE> C<EXIT_SUCCESS> C<MB_CUR_MAX> C<RAND_MAX>
2646 C<BUFSIZ> C<EOF> C<FILENAME_MAX> C<L_ctermid> C<L_cuserid> C<TMP_MAX>
2656 C<CLK_TCK> C<CLOCKS_PER_SEC>
2666 C<R_OK> C<SEEK_CUR> C<SEEK_END> C<SEEK_SET> C<STDIN_FILENO> C<STDOUT_FILENO> C<STDERR_FILENO> C<W_OK> C<X_OK>
2676 C<WNOHANG> C<WUNTRACED>
2682 Do not suspend the calling process until a child process
2683 changes state but instead return immediately.
2687 Catch stopped child processes.
2693 C<WIFEXITED> C<WEXITSTATUS> C<WIFSIGNALED> C<WTERMSIG> C<WIFSTOPPED> C<WSTOPSIG>
2699 C<WIFEXITED(${^CHILD_ERROR_NATIVE})> returns true if the child process
2700 exited normally (C<exit()> or by falling off the end of C<main()>)
2702 =item C<WEXITSTATUS>
2704 C<WEXITSTATUS(${^CHILD_ERROR_NATIVE})> returns the normal exit status of
2705 the child process (only meaningful if C<WIFEXITED(${^CHILD_ERROR_NATIVE})>
2708 =item C<WIFSIGNALED>
2710 C<WIFSIGNALED(${^CHILD_ERROR_NATIVE})> returns true if the child process
2711 terminated because of a signal
2715 C<WTERMSIG(${^CHILD_ERROR_NATIVE})> returns the signal the child process
2716 terminated for (only meaningful if
2717 C<WIFSIGNALED(${^CHILD_ERROR_NATIVE})>
2722 C<WIFSTOPPED(${^CHILD_ERROR_NATIVE})> returns true if the child process is
2723 currently stopped (can happen only if you specified the WUNTRACED flag
2728 C<WSTOPSIG(${^CHILD_ERROR_NATIVE})> returns the signal the child process
2729 was stopped for (only meaningful if
2730 C<WIFSTOPPED(${^CHILD_ERROR_NATIVE})>
2745 C<WSAEINTR> C<WSAEBADF> C<WSAEACCES> C<WSAEFAULT> C<WSAEINVAL> C<WSAEMFILE> C<WSAEWOULDBLOCK>
2746 C<WSAEINPROGRESS> C<WSAEALREADY> C<WSAENOTSOCK> C<WSAEDESTADDRREQ> C<WSAEMSGSIZE>
2747 C<WSAEPROTOTYPE> C<WSAENOPROTOOPT> C<WSAEPROTONOSUPPORT> C<WSAESOCKTNOSUPPORT>
2748 C<WSAEOPNOTSUPP> C<WSAEPFNOSUPPORT> C<WSAEAFNOSUPPORT> C<WSAEADDRINUSE>
2749 C<WSAEADDRNOTAVAIL> C<WSAENETDOWN> C<WSAENETUNREACH> C<WSAENETRESET> C<WSAECONNABORTED>
2750 C<WSAECONNRESET> C<WSAENOBUFS> C<WSAEISCONN> C<WSAENOTCONN> C<WSAESHUTDOWN>
2751 C<WSAETOOMANYREFS> C<WSAETIMEDOUT> C<WSAECONNREFUSED> C<WSAELOOP> C<WSAENAMETOOLONG>
2752 C<WSAEHOSTDOWN> C<WSAEHOSTUNREACH> C<WSAENOTEMPTY> C<WSAEPROCLIM> C<WSAEUSERS>
2753 C<WSAEDQUOT> C<WSAESTALE> C<WSAEREMOTE> C<WSAEDISCON> C<WSAENOMORE> C<WSAECANCELLED>
2754 C<WSAEINVALIDPROCTABLE> C<WSAEINVALIDPROVIDER> C<WSAEPROVIDERFAILEDINIT>