windows-nt/Source/XPSP1/NT/tools/x86/perl/lib/posix.pod

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=head1 NAME
POSIX - Perl interface to IEEE Std 1003.1
=head1 SYNOPSIS
use POSIX;
use POSIX qw(setsid);
use POSIX qw(:errno_h :fcntl_h);
printf "EINTR is %d\n", EINTR;
$sess_id = POSIX::setsid();
$fd = POSIX::open($path, O_CREAT|O_EXCL|O_WRONLY, 0644);
# note: that's a filedescriptor, *NOT* a filehandle
=head1 DESCRIPTION
The POSIX module permits you to access all (or nearly all) the standard
POSIX 1003.1 identifiers. Many of these identifiers have been given Perl-ish
interfaces. Things which are C<#defines> in C, like EINTR or O_NDELAY, are
automatically exported into your namespace. All functions are only exported
if you ask for them explicitly. Most likely people will prefer to use the
fully-qualified function names.
This document gives a condensed list of the features available in the POSIX
module. Consult your operating system's manpages for general information on
most features. Consult L<perlfunc> for functions which are noted as being
identical to Perl's builtin functions.
The first section describes POSIX functions from the 1003.1 specification.
The second section describes some classes for signal objects, TTY objects,
and other miscellaneous objects. The remaining sections list various
constants and macros in an organization which roughly follows IEEE Std
1003.1b-1993.
=head1 NOTE
The POSIX module is probably the most complex Perl module supplied with
the standard distribution. It incorporates autoloading, namespace games,
and dynamic loading of code that's in Perl, C, or both. It's a great
source of wisdom.
=head1 CAVEATS
A few functions are not implemented because they are C specific. If you
attempt to call these, they will print a message telling you that they
aren't implemented, and suggest using the Perl equivalent should one
exist. For example, trying to access the setjmp() call will elicit the
message "setjmp() is C-specific: use eval {} instead".
Furthermore, some evil vendors will claim 1003.1 compliance, but in fact
are not so: they will not pass the PCTS (POSIX Compliance Test Suites).
For example, one vendor may not define EDEADLK, or the semantics of the
errno values set by open(2) might not be quite right. Perl does not
attempt to verify POSIX compliance. That means you can currently
successfully say "use POSIX", and then later in your program you find
that your vendor has been lax and there's no usable ICANON macro after
all. This could be construed to be a bug.
=head1 FUNCTIONS
=over 8
=item _exit
This is identical to the C function C<_exit()>.
=item abort
This is identical to the C function C<abort()>.
=item abs
This is identical to Perl's builtin C<abs()> function.
=item access
Determines the accessibility of a file.
if( POSIX::access( "/", &POSIX::R_OK ) ){
print "have read permission\n";
}
Returns C<undef> on failure.
=item acos
This is identical to the C function C<acos()>.
=item alarm
This is identical to Perl's builtin C<alarm()> function.
=item asctime
This is identical to the C function C<asctime()>.
=item asin
This is identical to the C function C<asin()>.
=item assert
Unimplemented.
=item atan
This is identical to the C function C<atan()>.
=item atan2
This is identical to Perl's builtin C<atan2()> function.
=item atexit
atexit() is C-specific: use END {} instead.
=item atof
atof() is C-specific.
=item atoi
atoi() is C-specific.
=item atol
atol() is C-specific.
=item bsearch
bsearch() not supplied.
=item calloc
calloc() is C-specific.
=item ceil
This is identical to the C function C<ceil()>.
=item chdir
This is identical to Perl's builtin C<chdir()> function.
=item chmod
This is identical to Perl's builtin C<chmod()> function.
=item chown
This is identical to Perl's builtin C<chown()> function.
=item clearerr
Use method C<IO::Handle::clearerr()> instead.
=item clock
This is identical to the C function C<clock()>.
=item close
Close the file. This uses file descriptors such as those obtained by calling
C<POSIX::open>.
$fd = POSIX::open( "foo", &POSIX::O_RDONLY );
POSIX::close( $fd );
Returns C<undef> on failure.
=item closedir
This is identical to Perl's builtin C<closedir()> function.
=item cos
This is identical to Perl's builtin C<cos()> function.
=item cosh
This is identical to the C function C<cosh()>.
=item creat
Create a new file. This returns a file descriptor like the ones returned by
C<POSIX::open>. Use C<POSIX::close> to close the file.
$fd = POSIX::creat( "foo", 0611 );
POSIX::close( $fd );
=item ctermid
Generates the path name for the controlling terminal.
$path = POSIX::ctermid();
=item ctime
This is identical to the C function C<ctime()>.
=item cuserid
Get the character login name of the user.
$name = POSIX::cuserid();
=item difftime
This is identical to the C function C<difftime()>.
=item div
div() is C-specific.
=item dup
This is similar to the C function C<dup()>.
This uses file descriptors such as those obtained by calling
C<POSIX::open>.
Returns C<undef> on failure.
=item dup2
This is similar to the C function C<dup2()>.
This uses file descriptors such as those obtained by calling
C<POSIX::open>.
Returns C<undef> on failure.
=item errno
Returns the value of errno.
$errno = POSIX::errno();
=item execl
execl() is C-specific.
=item execle
execle() is C-specific.
=item execlp
execlp() is C-specific.
=item execv
execv() is C-specific.
=item execve
execve() is C-specific.
=item execvp
execvp() is C-specific.
=item exit
This is identical to Perl's builtin C<exit()> function.
=item exp
This is identical to Perl's builtin C<exp()> function.
=item fabs
This is identical to Perl's builtin C<abs()> function.
=item fclose
Use method C<IO::Handle::close()> instead.
=item fcntl
This is identical to Perl's builtin C<fcntl()> function.
=item fdopen
Use method C<IO::Handle::new_from_fd()> instead.
=item feof
Use method C<IO::Handle::eof()> instead.
=item ferror
Use method C<IO::Handle::error()> instead.
=item fflush
Use method C<IO::Handle::flush()> instead.
=item fgetc
Use method C<IO::Handle::getc()> instead.
=item fgetpos
Use method C<IO::Seekable::getpos()> instead.
=item fgets
Use method C<IO::Handle::gets()> instead.
=item fileno
Use method C<IO::Handle::fileno()> instead.
=item floor
This is identical to the C function C<floor()>.
=item fmod
This is identical to the C function C<fmod()>.
=item fopen
Use method C<IO::File::open()> instead.
=item fork
This is identical to Perl's builtin C<fork()> function.
=item fpathconf
Retrieves the value of a configurable limit on a file or directory. This
uses file descriptors such as those obtained by calling C<POSIX::open>.
The following will determine the maximum length of the longest allowable
pathname on the filesystem which holds C</tmp/foo>.
$fd = POSIX::open( "/tmp/foo", &POSIX::O_RDONLY );
$path_max = POSIX::fpathconf( $fd, &POSIX::_PC_PATH_MAX );
Returns C<undef> on failure.
=item fprintf
fprintf() is C-specific--use printf instead.
=item fputc
fputc() is C-specific--use print instead.
=item fputs
fputs() is C-specific--use print instead.
=item fread
fread() is C-specific--use read instead.
=item free
free() is C-specific.
=item freopen
freopen() is C-specific--use open instead.
=item frexp
Return the mantissa and exponent of a floating-point number.
($mantissa, $exponent) = POSIX::frexp( 3.14 );
=item fscanf
fscanf() is C-specific--use <> and regular expressions instead.
=item fseek
Use method C<IO::Seekable::seek()> instead.
=item fsetpos
Use method C<IO::Seekable::setpos()> instead.
=item fstat
Get file status. This uses file descriptors such as those obtained by
calling C<POSIX::open>. The data returned is identical to the data from
Perl's builtin C<stat> function.
$fd = POSIX::open( "foo", &POSIX::O_RDONLY );
@stats = POSIX::fstat( $fd );
=item ftell
Use method C<IO::Seekable::tell()> instead.
=item fwrite
fwrite() is C-specific--use print instead.
=item getc
This is identical to Perl's builtin C<getc()> function.
=item getchar
Returns one character from STDIN.
=item getcwd
Returns the name of the current working directory.
=item getegid
Returns the effective group id.
=item getenv
Returns the value of the specified enironment variable.
=item geteuid
Returns the effective user id.
=item getgid
Returns the user's real group id.
=item getgrgid
This is identical to Perl's builtin C<getgrgid()> function.
=item getgrnam
This is identical to Perl's builtin C<getgrnam()> function.
=item getgroups
Returns the ids of the user's supplementary groups.
=item getlogin
This is identical to Perl's builtin C<getlogin()> function.
=item getpgrp
This is identical to Perl's builtin C<getpgrp()> function.
=item getpid
Returns the process's id.
=item getppid
This is identical to Perl's builtin C<getppid()> function.
=item getpwnam
This is identical to Perl's builtin C<getpwnam()> function.
=item getpwuid
This is identical to Perl's builtin C<getpwuid()> function.
=item gets
Returns one line from STDIN.
=item getuid
Returns the user's id.
=item gmtime
This is identical to Perl's builtin C<gmtime()> function.
=item isalnum
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isalpha
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isatty
Returns a boolean indicating whether the specified filehandle is connected
to a tty.
=item iscntrl
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isdigit
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isgraph
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item islower
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isprint
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item ispunct
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isspace
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isupper
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item isxdigit
This is identical to the C function, except that it can apply to a single
character or to a whole string.
=item kill
This is identical to Perl's builtin C<kill()> function.
=item labs
labs() is C-specific, use abs instead.
=item ldexp
This is identical to the C function C<ldexp()>.
=item ldiv
ldiv() is C-specific, use / and int instead.
=item link
This is identical to Perl's builtin C<link()> function.
=item localeconv
Get numeric formatting information. Returns a reference to a hash
containing the current locale formatting values.
The database for the B<de> (Deutsch or German) locale.
$loc = POSIX::setlocale( &POSIX::LC_ALL, "de" );
print "Locale = $loc\n";
$lconv = POSIX::localeconv();
print "decimal_point = ", $lconv->{decimal_point}, "\n";
print "thousands_sep = ", $lconv->{thousands_sep}, "\n";
print "grouping = ", $lconv->{grouping}, "\n";
print "int_curr_symbol = ", $lconv->{int_curr_symbol}, "\n";
print "currency_symbol = ", $lconv->{currency_symbol}, "\n";
print "mon_decimal_point = ", $lconv->{mon_decimal_point}, "\n";
print "mon_thousands_sep = ", $lconv->{mon_thousands_sep}, "\n";
print "mon_grouping = ", $lconv->{mon_grouping}, "\n";
print "positive_sign = ", $lconv->{positive_sign}, "\n";
print "negative_sign = ", $lconv->{negative_sign}, "\n";
print "int_frac_digits = ", $lconv->{int_frac_digits}, "\n";
print "frac_digits = ", $lconv->{frac_digits}, "\n";
print "p_cs_precedes = ", $lconv->{p_cs_precedes}, "\n";
print "p_sep_by_space = ", $lconv->{p_sep_by_space}, "\n";
print "n_cs_precedes = ", $lconv->{n_cs_precedes}, "\n";
print "n_sep_by_space = ", $lconv->{n_sep_by_space}, "\n";
print "p_sign_posn = ", $lconv->{p_sign_posn}, "\n";
print "n_sign_posn = ", $lconv->{n_sign_posn}, "\n";
=item localtime
This is identical to Perl's builtin C<localtime()> function.
=item log
This is identical to Perl's builtin C<log()> function.
=item log10
This is identical to the C function C<log10()>.
=item longjmp
longjmp() is C-specific: use die instead.
=item lseek
Move the file's read/write position. This uses file descriptors such as
those obtained by calling C<POSIX::open>.
$fd = POSIX::open( "foo", &POSIX::O_RDONLY );
$off_t = POSIX::lseek( $fd, 0, &POSIX::SEEK_SET );
Returns C<undef> on failure.
=item malloc
malloc() is C-specific.
=item mblen
This is identical to the C function C<mblen()>.
=item mbstowcs
This is identical to the C function C<mbstowcs()>.
=item mbtowc
This is identical to the C function C<mbtowc()>.
=item memchr
memchr() is C-specific, use index() instead.
=item memcmp
memcmp() is C-specific, use eq instead.
=item memcpy
memcpy() is C-specific, use = instead.
=item memmove
memmove() is C-specific, use = instead.
=item memset
memset() is C-specific, use x instead.
=item mkdir
This is identical to Perl's builtin C<mkdir()> function.
=item mkfifo
This is similar to the C function C<mkfifo()>.
Returns C<undef> on failure.
=item mktime
Convert date/time info to a calendar time.
Synopsis:
mktime(sec, min, hour, mday, mon, year, wday = 0, yday = 0, isdst = 0)
The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero.
I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
year (C<year>) is given in years since 1900. I.e. The year 1995 is 95; the
year 2001 is 101. Consult your system's C<mktime()> manpage for details
about these and the other arguments.
Calendar time for December 12, 1995, at 10:30 am.
$time_t = POSIX::mktime( 0, 30, 10, 12, 11, 95 );
print "Date = ", POSIX::ctime($time_t);
Returns C<undef> on failure.
=item modf
Return the integral and fractional parts of a floating-point number.
($fractional, $integral) = POSIX::modf( 3.14 );
=item nice
This is similar to the C function C<nice()>.
Returns C<undef> on failure.
=item offsetof
offsetof() is C-specific.
=item open
Open a file for reading for writing. This returns file descriptors, not
Perl filehandles. Use C<POSIX::close> to close the file.
Open a file read-only with mode 0666.
$fd = POSIX::open( "foo" );
Open a file for read and write.
$fd = POSIX::open( "foo", &POSIX::O_RDWR );
Open a file for write, with truncation.
$fd = POSIX::open( "foo", &POSIX::O_WRONLY | &POSIX::O_TRUNC );
Create a new file with mode 0640. Set up the file for writing.
$fd = POSIX::open( "foo", &POSIX::O_CREAT | &POSIX::O_WRONLY, 0640 );
Returns C<undef> on failure.
=item opendir
Open a directory for reading.
$dir = POSIX::opendir( "/tmp" );
@files = POSIX::readdir( $dir );
POSIX::closedir( $dir );
Returns C<undef> on failure.
=item pathconf
Retrieves the value of a configurable limit on a file or directory.
The following will determine the maximum length of the longest allowable
pathname on the filesystem which holds C</tmp>.
$path_max = POSIX::pathconf( "/tmp", &POSIX::_PC_PATH_MAX );
Returns C<undef> on failure.
=item pause
This is similar to the C function C<pause()>.
Returns C<undef> on failure.
=item perror
This is identical to the C function C<perror()>.
=item pipe
Create an interprocess channel. This returns file descriptors like those
returned by C<POSIX::open>.
($fd0, $fd1) = POSIX::pipe();
POSIX::write( $fd0, "hello", 5 );
POSIX::read( $fd1, $buf, 5 );
=item pow
Computes $x raised to the power $exponent.
$ret = POSIX::pow( $x, $exponent );
=item printf
Prints the specified arguments to STDOUT.
=item putc
putc() is C-specific--use print instead.
=item putchar
putchar() is C-specific--use print instead.
=item puts
puts() is C-specific--use print instead.
=item qsort
qsort() is C-specific, use sort instead.
=item raise
Sends the specified signal to the current process.
=item rand
rand() is non-portable, use Perl's rand instead.
=item read
Read from a file. This uses file descriptors such as those obtained by
calling C<POSIX::open>. If the buffer C<$buf> is not large enough for the
read then Perl will extend it to make room for the request.
$fd = POSIX::open( "foo", &POSIX::O_RDONLY );
$bytes = POSIX::read( $fd, $buf, 3 );
Returns C<undef> on failure.
=item readdir
This is identical to Perl's builtin C<readdir()> function.
=item realloc
realloc() is C-specific.
=item remove
This is identical to Perl's builtin C<unlink()> function.
=item rename
This is identical to Perl's builtin C<rename()> function.
=item rewind
Seeks to the beginning of the file.
=item rewinddir
This is identical to Perl's builtin C<rewinddir()> function.
=item rmdir
This is identical to Perl's builtin C<rmdir()> function.
=item scanf
scanf() is C-specific--use <> and regular expressions instead.
=item setgid
Sets the real group id for this process.
=item setjmp
setjmp() is C-specific: use eval {} instead.
=item setlocale
Modifies and queries program's locale.
The following will set the traditional UNIX system locale behavior
(the second argument C<"C">).
$loc = POSIX::setlocale( &POSIX::LC_ALL, "C" );
The following will query (the missing second argument) the current
LC_CTYPE category.
$loc = POSIX::setlocale( &POSIX::LC_CTYPE);
The following will set the LC_CTYPE behaviour according to the locale
environment variables (the second argument C<"">).
Please see your systems L<setlocale(3)> documentation for the locale
environment variables' meaning or consult L<perllocale>.
$loc = POSIX::setlocale( &POSIX::LC_CTYPE, "");
The following will set the LC_COLLATE behaviour to Argentinian
Spanish. B<NOTE>: The naming and availability of locales depends on
your operating system. Please consult L<perllocale> for how to find
out which locales are available in your system.
$loc = POSIX::setlocale( &POSIX::LC_ALL, "es_AR.ISO8859-1" );
=item setpgid
This is similar to the C function C<setpgid()>.
Returns C<undef> on failure.
=item setsid
This is identical to the C function C<setsid()>.
=item setuid
Sets the real user id for this process.
=item sigaction
Detailed signal management. This uses C<POSIX::SigAction> objects for the
C<action> and C<oldaction> arguments. Consult your system's C<sigaction>
manpage for details.
Synopsis:
sigaction(sig, action, oldaction = 0)
Returns C<undef> on failure.
=item siglongjmp
siglongjmp() is C-specific: use die instead.
=item sigpending
Examine signals that are blocked and pending. This uses C<POSIX::SigSet>
objects for the C<sigset> argument. Consult your system's C<sigpending>
manpage for details.
Synopsis:
sigpending(sigset)
Returns C<undef> on failure.
=item sigprocmask
Change and/or examine calling process's signal mask. This uses
C<POSIX::SigSet> objects for the C<sigset> and C<oldsigset> arguments.
Consult your system's C<sigprocmask> manpage for details.
Synopsis:
sigprocmask(how, sigset, oldsigset = 0)
Returns C<undef> on failure.
=item sigsetjmp
sigsetjmp() is C-specific: use eval {} instead.
=item sigsuspend
Install a signal mask and suspend process until signal arrives. This uses
C<POSIX::SigSet> objects for the C<signal_mask> argument. Consult your
system's C<sigsuspend> manpage for details.
Synopsis:
sigsuspend(signal_mask)
Returns C<undef> on failure.
=item sin
This is identical to Perl's builtin C<sin()> function.
=item sinh
This is identical to the C function C<sinh()>.
=item sleep
This is identical to Perl's builtin C<sleep()> function.
=item sprintf
This is identical to Perl's builtin C<sprintf()> function.
=item sqrt
This is identical to Perl's builtin C<sqrt()> function.
=item srand
srand().
=item sscanf
sscanf() is C-specific--use regular expressions instead.
=item stat
This is identical to Perl's builtin C<stat()> function.
=item strcat
strcat() is C-specific, use .= instead.
=item strchr
strchr() is C-specific, use index() instead.
=item strcmp
strcmp() is C-specific, use eq instead.
=item strcoll
This is identical to the C function C<strcoll()>.
=item strcpy
strcpy() is C-specific, use = instead.
=item strcspn
strcspn() is C-specific, use regular expressions instead.
=item strerror
Returns the error string for the specified errno.
=item strftime
Convert date and time information to string. Returns the string.
Synopsis:
strftime(fmt, sec, min, hour, mday, mon, year, wday = -1, yday = -1, isdst = -1)
The month (C<mon>), weekday (C<wday>), and yearday (C<yday>) begin at zero.
I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The
year (C<year>) is given in years since 1900. I.e., the year 1995 is 95; the
year 2001 is 101. Consult your system's C<strftime()> manpage for details
about these and the other arguments. The given arguments are made consistent
by calling C<mktime()> before calling your system's C<strftime()> function.
The string for Tuesday, December 12, 1995.
$str = POSIX::strftime( "%A, %B %d, %Y", 0, 0, 0, 12, 11, 95, 2 );
print "$str\n";
=item strlen
strlen() is C-specific, use length instead.
=item strncat
strncat() is C-specific, use .= instead.
=item strncmp
strncmp() is C-specific, use eq instead.
=item strncpy
strncpy() is C-specific, use = instead.
=item stroul
stroul() is C-specific.
=item strpbrk
strpbrk() is C-specific.
=item strrchr
strrchr() is C-specific, use rindex() instead.
=item strspn
strspn() is C-specific.
=item strstr
This is identical to Perl's builtin C<index()> function.
=item strtod
String to double translation. Returns the parsed number and the number
of characters in the unparsed portion of the string. Truly
POSIX-compliant systems set $! ($ERRNO) to indicate a translation
error, so clear $! before calling strtod. However, non-POSIX systems
may not check for overflow, and therefore will never set $!.
strtod should respect any POSIX I<setlocale()> settings.
To parse a string $str as a floating point number use
$! = 0;
($num, $n_unparsed) = POSIX::strtod($str);
The second returned item and $! can be used to check for valid input:
if (($str eq '') || ($n_unparsed != 0) || !$!) {
die "Non-numeric input $str" . $! ? ": $!\n" : "\n";
}
When called in a scalar context strtod returns the parsed number.
=item strtok
strtok() is C-specific.
=item strtol
String to (long) integer translation. Returns the parsed number and
the number of characters in the unparsed portion of the string. Truly
POSIX-compliant systems set $! ($ERRNO) to indicate a translation
error, so clear $! before calling strtol. However, non-POSIX systems
may not check for overflow, and therefore will never set $!.
strtol should respect any POSIX I<setlocale()> settings.
To parse a string $str as a number in some base $base use
$! = 0;
($num, $n_unparsed) = POSIX::strtol($str, $base);
The base should be zero or between 2 and 36, inclusive. When the base
is zero or omitted strtol will use the string itself to determine the
base: a leading "0x" or "0X" means hexadecimal; a leading "0" means
octal; any other leading characters mean decimal. Thus, "1234" is
parsed as a decimal number, "01234" as an octal number, and "0x1234"
as a hexadecimal number.
The second returned item and $! can be used to check for valid input:
if (($str eq '') || ($n_unparsed != 0) || !$!) {
die "Non-numeric input $str" . $! ? ": $!\n" : "\n";
}
When called in a scalar context strtol returns the parsed number.
=item strtoul
String to unsigned (long) integer translation. strtoul is identical
to strtol except that strtoul only parses unsigned integers. See
I<strtol> for details.
Note: Some vendors supply strtod and strtol but not strtoul.
Other vendors that do suply strtoul parse "-1" as a valid value.
=item strxfrm
String transformation. Returns the transformed string.
$dst = POSIX::strxfrm( $src );
=item sysconf
Retrieves values of system configurable variables.
The following will get the machine's clock speed.
$clock_ticks = POSIX::sysconf( &POSIX::_SC_CLK_TCK );
Returns C<undef> on failure.
=item system
This is identical to Perl's builtin C<system()> function.
=item tan
This is identical to the C function C<tan()>.
=item tanh
This is identical to the C function C<tanh()>.
=item tcdrain
This is similar to the C function C<tcdrain()>.
Returns C<undef> on failure.
=item tcflow
This is similar to the C function C<tcflow()>.
Returns C<undef> on failure.
=item tcflush
This is similar to the C function C<tcflush()>.
Returns C<undef> on failure.
=item tcgetpgrp
This is identical to the C function C<tcgetpgrp()>.
=item tcsendbreak
This is similar to the C function C<tcsendbreak()>.
Returns C<undef> on failure.
=item tcsetpgrp
This is similar to the C function C<tcsetpgrp()>.
Returns C<undef> on failure.
=item time
This is identical to Perl's builtin C<time()> function.
=item times
The times() function returns elapsed realtime since some point in the past
(such as system startup), user and system times for this process, and user
and system times used by child processes. All times are returned in clock
ticks.
($realtime, $user, $system, $cuser, $csystem) = POSIX::times();
Note: Perl's builtin C<times()> function returns four values, measured in
seconds.
=item tmpfile
Use method C<IO::File::new_tmpfile()> instead.
=item tmpnam
Returns a name for a temporary file.
$tmpfile = POSIX::tmpnam();
=item tolower
This is identical to Perl's builtin C<lc()> function.
=item toupper
This is identical to Perl's builtin C<uc()> function.
=item ttyname
This is identical to the C function C<ttyname()>.
=item tzname
Retrieves the time conversion information from the C<tzname> variable.
POSIX::tzset();
($std, $dst) = POSIX::tzname();
=item tzset
This is identical to the C function C<tzset()>.
=item umask
This is identical to Perl's builtin C<umask()> function.
=item uname
Get name of current operating system.
($sysname, $nodename, $release, $version, $machine ) = POSIX::uname();
=item ungetc
Use method C<IO::Handle::ungetc()> instead.
=item unlink
This is identical to Perl's builtin C<unlink()> function.
=item utime
This is identical to Perl's builtin C<utime()> function.
=item vfprintf
vfprintf() is C-specific.
=item vprintf
vprintf() is C-specific.
=item vsprintf
vsprintf() is C-specific.
=item wait
This is identical to Perl's builtin C<wait()> function.
=item waitpid
Wait for a child process to change state. This is identical to Perl's
builtin C<waitpid()> function.
$pid = POSIX::waitpid( -1, &POSIX::WNOHANG );
print "status = ", ($? / 256), "\n";
=item wcstombs
This is identical to the C function C<wcstombs()>.
=item wctomb
This is identical to the C function C<wctomb()>.
=item write
Write to a file. This uses file descriptors such as those obtained by
calling C<POSIX::open>.
$fd = POSIX::open( "foo", &POSIX::O_WRONLY );
$buf = "hello";
$bytes = POSIX::write( $b, $buf, 5 );
Returns C<undef> on failure.
=back
=head1 CLASSES
=head2 POSIX::SigAction
=over 8
=item new
Creates a new C<POSIX::SigAction> object which corresponds to the C
C<struct sigaction>. This object will be destroyed automatically when it is
no longer needed. The first parameter is the fully-qualified name of a sub
which is a signal-handler. The second parameter is a C<POSIX::SigSet>
object, it defaults to the empty set. The third parameter contains the
C<sa_flags>, it defaults to 0.
$sigset = POSIX::SigSet->new(SIGINT, SIGQUIT);
$sigaction = POSIX::SigAction->new( 'main::handler', $sigset, &POSIX::SA_NOCLDSTOP );
This C<POSIX::SigAction> object should be used with the C<POSIX::sigaction()>
function.
=back
=head2 POSIX::SigSet
=over 8
=item new
Create a new SigSet object. This object will be destroyed automatically
when it is no longer needed. Arguments may be supplied to initialize the
set.
Create an empty set.
$sigset = POSIX::SigSet->new;
Create a set with SIGUSR1.
$sigset = POSIX::SigSet->new( &POSIX::SIGUSR1 );
=item addset
Add a signal to a SigSet object.
$sigset->addset( &POSIX::SIGUSR2 );
Returns C<undef> on failure.
=item delset
Remove a signal from the SigSet object.
$sigset->delset( &POSIX::SIGUSR2 );
Returns C<undef> on failure.
=item emptyset
Initialize the SigSet object to be empty.
$sigset->emptyset();
Returns C<undef> on failure.
=item fillset
Initialize the SigSet object to include all signals.
$sigset->fillset();
Returns C<undef> on failure.
=item ismember
Tests the SigSet object to see if it contains a specific signal.
if( $sigset->ismember( &POSIX::SIGUSR1 ) ){
print "contains SIGUSR1\n";
}
=back
=head2 POSIX::Termios
=over 8
=item new
Create a new Termios object. This object will be destroyed automatically
when it is no longer needed. A Termios object corresponds to the termios
C struct. new() mallocs a new one, getattr() fills it from a file descriptor,
and setattr() sets a file descriptor's parameters to match Termios' contents.
$termios = POSIX::Termios->new;
=item getattr
Get terminal control attributes.
Obtain the attributes for stdin.
$termios->getattr()
Obtain the attributes for stdout.
$termios->getattr( 1 )
Returns C<undef> on failure.
=item getcc
Retrieve a value from the c_cc field of a termios object. The c_cc field is
an array so an index must be specified.
$c_cc[1] = $termios->getcc(1);
=item getcflag
Retrieve the c_cflag field of a termios object.
$c_cflag = $termios->getcflag;
=item getiflag
Retrieve the c_iflag field of a termios object.
$c_iflag = $termios->getiflag;
=item getispeed
Retrieve the input baud rate.
$ispeed = $termios->getispeed;
=item getlflag
Retrieve the c_lflag field of a termios object.
$c_lflag = $termios->getlflag;
=item getoflag
Retrieve the c_oflag field of a termios object.
$c_oflag = $termios->getoflag;
=item getospeed
Retrieve the output baud rate.
$ospeed = $termios->getospeed;
=item setattr
Set terminal control attributes.
Set attributes immediately for stdout.
$termios->setattr( 1, &POSIX::TCSANOW );
Returns C<undef> on failure.
=item setcc
Set a value in the c_cc field of a termios object. The c_cc field is an
array so an index must be specified.
$termios->setcc( &POSIX::VEOF, 1 );
=item setcflag
Set the c_cflag field of a termios object.
$termios->setcflag( $c_cflag | &POSIX::CLOCAL );
=item setiflag
Set the c_iflag field of a termios object.
$termios->setiflag( $c_iflag | &POSIX::BRKINT );
=item setispeed
Set the input baud rate.
$termios->setispeed( &POSIX::B9600 );
Returns C<undef> on failure.
=item setlflag
Set the c_lflag field of a termios object.
$termios->setlflag( $c_lflag | &POSIX::ECHO );
=item setoflag
Set the c_oflag field of a termios object.
$termios->setoflag( $c_oflag | &POSIX::OPOST );
=item setospeed
Set the output baud rate.
$termios->setospeed( &POSIX::B9600 );
Returns C<undef> on failure.
=item Baud rate values
B38400 B75 B200 B134 B300 B1800 B150 B0 B19200 B1200 B9600 B600 B4800 B50 B2400 B110
=item Terminal interface values
TCSADRAIN TCSANOW TCOON TCIOFLUSH TCOFLUSH TCION TCIFLUSH TCSAFLUSH TCIOFF TCOOFF
=item c_cc field values
VEOF VEOL VERASE VINTR VKILL VQUIT VSUSP VSTART VSTOP VMIN VTIME NCCS
=item c_cflag field values
CLOCAL CREAD CSIZE CS5 CS6 CS7 CS8 CSTOPB HUPCL PARENB PARODD
=item c_iflag field values
BRKINT ICRNL IGNBRK IGNCR IGNPAR INLCR INPCK ISTRIP IXOFF IXON PARMRK
=item c_lflag field values
ECHO ECHOE ECHOK ECHONL ICANON IEXTEN ISIG NOFLSH TOSTOP
=item c_oflag field values
OPOST
=back
=head1 PATHNAME CONSTANTS
=over 8
=item Constants
_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
=back
=head1 POSIX CONSTANTS
=over 8
=item Constants
_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
=back
=head1 SYSTEM CONFIGURATION
=over 8
=item Constants
_SC_ARG_MAX _SC_CHILD_MAX _SC_CLK_TCK _SC_JOB_CONTROL _SC_NGROUPS_MAX _SC_OPEN_MAX _SC_SAVED_IDS _SC_STREAM_MAX _SC_TZNAME_MAX _SC_VERSION
=back
=head1 ERRNO
=over 8
=item Constants
E2BIG EACCES EADDRINUSE EADDRNOTAVAIL EAFNOSUPPORT EAGAIN EALREADY EBADF
EBUSY ECHILD ECONNABORTED ECONNREFUSED ECONNRESET EDEADLK EDESTADDRREQ
EDOM EDQUOT EEXIST EFAULT EFBIG EHOSTDOWN EHOSTUNREACH EINPROGRESS EINTR
EINVAL EIO EISCONN EISDIR ELOOP EMFILE EMLINK EMSGSIZE ENAMETOOLONG
ENETDOWN ENETRESET ENETUNREACH ENFILE ENOBUFS ENODEV ENOENT ENOEXEC
ENOLCK ENOMEM ENOPROTOOPT ENOSPC ENOSYS ENOTBLK ENOTCONN ENOTDIR
ENOTEMPTY ENOTSOCK ENOTTY ENXIO EOPNOTSUPP EPERM EPFNOSUPPORT EPIPE
EPROCLIM EPROTONOSUPPORT EPROTOTYPE ERANGE EREMOTE ERESTART EROFS
ESHUTDOWN ESOCKTNOSUPPORT ESPIPE ESRCH ESTALE ETIMEDOUT ETOOMANYREFS
ETXTBSY EUSERS EWOULDBLOCK EXDEV
=back
=head1 FCNTL
=over 8
=item Constants
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
=back
=head1 FLOAT
=over 8
=item Constants
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
=back
=head1 LIMITS
=over 8
=item Constants
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
=back
=head1 LOCALE
=over 8
=item Constants
LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME
=back
=head1 MATH
=over 8
=item Constants
HUGE_VAL
=back
=head1 SIGNAL
=over 8
=item Constants
SA_NOCLDSTOP SA_NOCLDWAIT SA_NODEFER SA_ONSTACK SA_RESETHAND SA_RESTART
SA_SIGINFO SIGABRT SIGALRM SIGCHLD SIGCONT SIGFPE SIGHUP SIGILL SIGINT
SIGKILL SIGPIPE SIGQUIT SIGSEGV SIGSTOP SIGTERM SIGTSTP SIGTTIN SIGTTOU
SIGUSR1 SIGUSR2 SIG_BLOCK SIG_DFL SIG_ERR SIG_IGN SIG_SETMASK
SIG_UNBLOCK
=back
=head1 STAT
=over 8
=item Constants
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
=item Macros
S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISREG
=back
=head1 STDLIB
=over 8
=item Constants
EXIT_FAILURE EXIT_SUCCESS MB_CUR_MAX RAND_MAX
=back
=head1 STDIO
=over 8
=item Constants
BUFSIZ EOF FILENAME_MAX L_ctermid L_cuserid L_tmpname TMP_MAX
=back
=head1 TIME
=over 8
=item Constants
CLK_TCK CLOCKS_PER_SEC
=back
=head1 UNISTD
=over 8
=item Constants
R_OK SEEK_CUR SEEK_END SEEK_SET STDIN_FILENO STDOUT_FILENO STRERR_FILENO W_OK X_OK
=back
=head1 WAIT
=over 8
=item Constants
WNOHANG WUNTRACED
=item Macros
WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG WIFSTOPPED WSTOPSIG
=back
=head1 CREATION
This document generated by ./mkposixman.PL version 19960129.