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• NAME
• SYNOPSIS
• DESCRIPTION
• NOTE
• CAVEATS
• FUNCTIONS
• CLASSES
  • POSIX::SigAction
  • POSIX::SigSet
  • POSIX::Termios
• PATHNAME CONSTANTS
• POSIX CONSTANTS
• SYSTEM CONFIGURATION
• ERRNO
• FCNTL
• FLOAT
• LIMITS
• LOCALE
• MATH
• SIGNAL
• STAT
• STDLIB
• STDIO
• TIME
• UNISTD
• WAIT
• CREATION

---

NAME

POSIX - Perl interface to IEEE Std 1003.1

---

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

---

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 #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 the perlfunc manpage 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.

---

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.

---

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.

---

FUNCTIONS

_exit

This is identical to the C function _exit().

abort

This is identical to the C function abort().

abs

This is identical to Perl's builtin abs() function.

access

Determines the accessibility of a file.

        if( POSIX::access( "/", &POSIX::R_OK ) ){
                print "have read permission\n";
        }

Returns undef on failure.

acos

This is identical to the C function acos().

alarm

This is identical to Perl's builtin alarm() function.

asctime

This is identical to the C function asctime().

asin

This is identical to the C function asin().

assert

Unimplemented.

atan

This is identical to the C function atan().

atan2

This is identical to Perl's builtin atan2() function.

atexit

atexit() is C-specific: use END {} instead.

atof

atof() is C-specific.

atoi

atoi() is C-specific.

atol

atol() is C-specific.

bsearch

bsearch() not supplied.

calloc

calloc() is C-specific.

ceil

This is identical to the C function ceil().

chdir

This is identical to Perl's builtin chdir() function.

chmod

This is identical to Perl's builtin chmod() function.

chown

This is identical to Perl's builtin chown() function.

clearerr

Use method IO::Handle::clearerr() instead.

clock

This is identical to the C function clock().

close

Close the file. This uses file descriptors such as those obtained by calling POSIX::open.

        $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
        POSIX::close( $fd );

Returns undef on failure.

closedir

This is identical to Perl's builtin closedir() function.

cos

This is identical to Perl's builtin cos() function.

cosh

This is identical to the C function cosh().

creat

Create a new file. This returns a file descriptor like the ones returned by POSIX::open. Use POSIX::close to close the file.

        $fd = POSIX::creat( "foo", 0611 );
        POSIX::close( $fd );

ctermid

Generates the path name for the controlling terminal.

        $path = POSIX::ctermid();

ctime

This is identical to the C function ctime().

cuserid

Get the character login name of the user.

        $name = POSIX::cuserid();

difftime

This is identical to the C function difftime().

div

div() is C-specific.

dup

This is similar to the C function dup().

This uses file descriptors such as those obtained by calling POSIX::open.

Returns undef on failure.

dup2

This is similar to the C function dup2().

This uses file descriptors such as those obtained by calling POSIX::open.

Returns undef on failure.

errno

Returns the value of errno.

        $errno = POSIX::errno();

execl

execl() is C-specific.

execle

execle() is C-specific.

execlp

execlp() is C-specific.

execv

execv() is C-specific.

execve

execve() is C-specific.

execvp

execvp() is C-specific.

exit

This is identical to Perl's builtin exit() function.

exp

This is identical to Perl's builtin exp() function.

fabs

This is identical to Perl's builtin abs() function.

fclose

Use method IO::Handle::close() instead.

fcntl

This is identical to Perl's builtin fcntl() function.

fdopen

Use method IO::Handle::new_from_fd() instead.

feof

Use method IO::Handle::eof() instead.

ferror

Use method IO::Handle::error() instead.

fflush

Use method IO::Handle::flush() instead.

fgetc

Use method IO::Handle::getc() instead.

fgetpos

Use method IO::Seekable::getpos() instead.

fgets

Use method IO::Handle::gets() instead.

fileno

Use method IO::Handle::fileno() instead.

floor

This is identical to the C function floor().

fmod

This is identical to the C function fmod().

fopen

Use method IO::File::open() instead.

fork

This is identical to Perl's builtin fork() function.

fpathconf

Retrieves the value of a configurable limit on a file or directory. This uses file descriptors such as those obtained by calling POSIX::open.

The following will determine the maximum length of the longest allowable pathname on the filesystem which holds /tmp/foo.

        $fd = POSIX::open( "/tmp/foo", &POSIX::O_RDONLY );
        $path_max = POSIX::fpathconf( $fd, &POSIX::_PC_PATH_MAX );

Returns undef on failure.

fprintf

fprintf() is C-specific--use printf instead.

fputc

fputc() is C-specific--use print instead.

fputs

fputs() is C-specific--use print instead.

fread

fread() is C-specific--use read instead.

free

free() is C-specific.

freopen

freopen() is C-specific--use open instead.

frexp

Return the mantissa and exponent of a floating-point number.

        ($mantissa, $exponent) = POSIX::frexp( 3.14 );

fscanf

fscanf() is C-specific--use <> and regular expressions instead.

fseek

Use method IO::Seekable::seek() instead.

fsetpos

Use method IO::Seekable::setpos() instead.

fstat

Get file status. This uses file descriptors such as those obtained by calling POSIX::open. The data returned is identical to the data from Perl's builtin stat function.

        $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
        @stats = POSIX::fstat( $fd );

ftell

Use method IO::Seekable::tell() instead.

fwrite

fwrite() is C-specific--use print instead.

getc

This is identical to Perl's builtin getc() function.

getchar

Returns one character from STDIN.

getcwd

Returns the name of the current working directory.

getegid

Returns the effective group id.

getenv

Returns the value of the specified enironment variable.

geteuid

Returns the effective user id.

getgid

Returns the user's real group id.

getgrgid

This is identical to Perl's builtin getgrgid() function.

getgrnam

This is identical to Perl's builtin getgrnam() function.

getgroups

Returns the ids of the user's supplementary groups.

getlogin

This is identical to Perl's builtin getlogin() function.

getpgrp

This is identical to Perl's builtin getpgrp() function.

getpid

Returns the process's id.

getppid

This is identical to Perl's builtin getppid() function.

getpwnam

This is identical to Perl's builtin getpwnam() function.

getpwuid

This is identical to Perl's builtin getpwuid() function.

gets

Returns one line from STDIN.

getuid

Returns the user's id.

gmtime

This is identical to Perl's builtin gmtime() function.

isalnum

This is identical to the C function, except that it can apply to a single character or to a whole string.

isalpha

This is identical to the C function, except that it can apply to a single character or to a whole string.

isatty

Returns a boolean indicating whether the specified filehandle is connected to a tty.

iscntrl

This is identical to the C function, except that it can apply to a single character or to a whole string.

isdigit

This is identical to the C function, except that it can apply to a single character or to a whole string.

isgraph

This is identical to the C function, except that it can apply to a single character or to a whole string.

islower

This is identical to the C function, except that it can apply to a single character or to a whole string.

isprint

This is identical to the C function, except that it can apply to a single character or to a whole string.

ispunct

This is identical to the C function, except that it can apply to a single character or to a whole string.

isspace

This is identical to the C function, except that it can apply to a single character or to a whole string.

isupper

This is identical to the C function, except that it can apply to a single character or to a whole string.

isxdigit

This is identical to the C function, except that it can apply to a single character or to a whole string.

kill

This is identical to Perl's builtin kill() function.

labs

labs() is C-specific, use abs instead.

ldexp

This is identical to the C function ldexp().

ldiv

ldiv() is C-specific, use / and int instead.

link

This is identical to Perl's builtin link() function.

localeconv

Get numeric formatting information. Returns a reference to a hash containing the current locale formatting values.

The database for the 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";

localtime

This is identical to Perl's builtin localtime() function.

log

This is identical to Perl's builtin log() function.

log10

This is identical to the C function log10().

longjmp

longjmp() is C-specific: use die instead.

lseek

Move the file's read/write position. This uses file descriptors such as those obtained by calling POSIX::open.

        $fd = POSIX::open( "foo", &POSIX::O_RDONLY );
        $off_t = POSIX::lseek( $fd, 0, &POSIX::SEEK_SET );

Returns undef on failure.

malloc

malloc() is C-specific.

mblen

This is identical to the C function mblen().

mbstowcs

This is identical to the C function mbstowcs().

mbtowc

This is identical to the C function mbtowc().

memchr

memchr() is C-specific, use index() instead.

memcmp

memcmp() is C-specific, use eq instead.

memcpy

memcpy() is C-specific, use = instead.

memmove

memmove() is C-specific, use = instead.

memset

memset() is C-specific, use x instead.

mkdir

This is identical to Perl's builtin mkdir() function.

mkfifo

This is similar to the C function mkfifo().

Returns undef on failure.

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 (mon), weekday (wday), and yearday (yday) begin at zero. I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The year (year) is given in years since 1900. I.e. The year 1995 is 95; the year 2001 is 101. Consult your system's 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 undef on failure.

modf

Return the integral and fractional parts of a floating-point number.

        ($fractional, $integral) = POSIX::modf( 3.14 );

nice

This is similar to the C function nice().

Returns undef on failure.

offsetof

offsetof() is C-specific.

open

Open a file for reading for writing. This returns file descriptors, not Perl filehandles. Use 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 undef on failure.

opendir

Open a directory for reading.

        $dir = POSIX::opendir( "/tmp" );
        @files = POSIX::readdir( $dir );
        POSIX::closedir( $dir );

Returns undef on failure.

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 /tmp.

        $path_max = POSIX::pathconf( "/tmp", &POSIX::_PC_PATH_MAX );

Returns undef on failure.

pause

This is similar to the C function pause().

Returns undef on failure.

perror

This is identical to the C function perror().

pipe

Create an interprocess channel. This returns file descriptors like those returned by POSIX::open.

        ($fd0, $fd1) = POSIX::pipe();
        POSIX::write( $fd0, "hello", 5 );
        POSIX::read( $fd1, $buf, 5 );

pow

Computes $x raised to the power $exponent.

        $ret = POSIX::pow( $x, $exponent );

printf

Prints the specified arguments to STDOUT.

putc

putc() is C-specific--use print instead.

putchar

putchar() is C-specific--use print instead.

puts

puts() is C-specific--use print instead.

qsort

qsort() is C-specific, use sort instead.

raise

Sends the specified signal to the current process.

rand

rand() is non-portable, use Perl's rand instead.

read

Read from a file. This uses file descriptors such as those obtained by calling POSIX::open. If the buffer $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 undef on failure.

readdir

This is identical to Perl's builtin readdir() function.

realloc

realloc() is C-specific.

remove

This is identical to Perl's builtin unlink() function.

rename

This is identical to Perl's builtin rename() function.

rewind

Seeks to the beginning of the file.

rewinddir

This is identical to Perl's builtin rewinddir() function.

rmdir

This is identical to Perl's builtin rmdir() function.

scanf

scanf() is C-specific--use <> and regular expressions instead.

setgid

Sets the real group id for this process.

setjmp

setjmp() is C-specific: use eval {} instead.

setlocale

Modifies and queries program's locale.

The following will set the traditional UNIX system locale behavior (the second argument "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 ""). Please see your systems setlocale(3) documentation for the locale environment variables' meaning or consult the perllocale manpage.

        $loc = POSIX::setlocale( &POSIX::LC_CTYPE, "");

The following will set the LC_COLLATE behaviour to Argentinian Spanish. NOTE: The naming and availability of locales depends on your operating system. Please consult the perllocale manpage for how to find out which locales are available in your system.

        $loc = POSIX::setlocale( &POSIX::LC_ALL, "es_AR.ISO8859-1" );

setpgid

This is similar to the C function setpgid().

Returns undef on failure.

setsid

This is identical to the C function setsid().

setuid

Sets the real user id for this process.

sigaction

Detailed signal management. This uses POSIX::SigAction objects for the action and oldaction arguments. Consult your system's sigaction manpage for details.

Synopsis:

        sigaction(sig, action, oldaction = 0)

Returns undef on failure.

siglongjmp

siglongjmp() is C-specific: use die instead.

sigpending

Examine signals that are blocked and pending. This uses POSIX::SigSet objects for the sigset argument. Consult your system's sigpending manpage for details.

Synopsis:

        sigpending(sigset)

Returns undef on failure.

sigprocmask

Change and/or examine calling process's signal mask. This uses POSIX::SigSet objects for the sigset and oldsigset arguments. Consult your system's sigprocmask manpage for details.

Synopsis:

        sigprocmask(how, sigset, oldsigset = 0)

Returns undef on failure.

sigsetjmp

sigsetjmp() is C-specific: use eval {} instead.

sigsuspend

Install a signal mask and suspend process until signal arrives. This uses POSIX::SigSet objects for the signal_mask argument. Consult your system's sigsuspend manpage for details.

Synopsis:

        sigsuspend(signal_mask)

Returns undef on failure.

sin

This is identical to Perl's builtin sin() function.

sinh

This is identical to the C function sinh().

sleep

This is identical to Perl's builtin sleep() function.

sprintf

This is identical to Perl's builtin sprintf() function.

sqrt

This is identical to Perl's builtin sqrt() function.

srand

srand().

sscanf

sscanf() is C-specific--use regular expressions instead.

stat

This is identical to Perl's builtin stat() function.

strcat

strcat() is C-specific, use .= instead.

strchr

strchr() is C-specific, use index() instead.

strcmp

strcmp() is C-specific, use eq instead.

strcoll

This is identical to the C function strcoll().

strcpy

strcpy() is C-specific, use = instead.

strcspn

strcspn() is C-specific, use regular expressions instead.

strerror

Returns the error string for the specified errno.

strftime

Convert date and time information to string. Returns the string.

Synopsis:

        strftime(fmt, sec, min, hour, mday, mon, year, wday = 0, yday = 0, isdst = 0)

The month (mon), weekday (wday), and yearday (yday) begin at zero. I.e. January is 0, not 1; Sunday is 0, not 1; January 1st is 0, not 1. The year (year) is given in years since 1900. I.e. The year 1995 is 95; the year 2001 is 101. Consult your system's strftime() manpage for details about these and the other arguments.

The string for Tuesday, December 12, 1995.

        $str = POSIX::strftime( "%A, %B %d, %Y", 0, 0, 0, 12, 11, 95, 2 );
        print "$str\n";

strlen

strlen() is C-specific, use length instead.

strncat

strncat() is C-specific, use .= instead.

strncmp

strncmp() is C-specific, use eq instead.

strncpy

strncpy() is C-specific, use = instead.

stroul

stroul() is C-specific.

strpbrk

strpbrk() is C-specific.

strrchr

strrchr() is C-specific, use rindex() instead.

strspn

strspn() is C-specific.

strstr

This is identical to Perl's builtin index() function.

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 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.

strtok

strtok() is C-specific.

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 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.

strtoul

String to unsigned (long) integer translation. strtoul is identical to strtol except that strtoul only parses unsigned integers. See 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.

strxfrm

String transformation. Returns the transformed string.

        $dst = POSIX::strxfrm( $src );

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 undef on failure.

system

This is identical to Perl's builtin system() function.

tan

This is identical to the C function tan().

tanh

This is identical to the C function tanh().

tcdrain

This is similar to the C function tcdrain().

Returns undef on failure.

tcflow

This is similar to the C function tcflow().

Returns undef on failure.

tcflush

This is similar to the C function tcflush().

Returns undef on failure.

tcgetpgrp

This is identical to the C function tcgetpgrp().

tcsendbreak

This is similar to the C function tcsendbreak().

Returns undef on failure.

tcsetpgrp

This is similar to the C function tcsetpgrp().

Returns undef on failure.

time

This is identical to Perl's builtin time() function.

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 times() function returns four values, measured in seconds.

tmpfile

Use method IO::File::new_tmpfile() instead.

tmpnam

Returns a name for a temporary file.

        $tmpfile = POSIX::tmpnam();

tolower

This is identical to Perl's builtin lc() function.

toupper

This is identical to Perl's builtin uc() function.

ttyname

This is identical to the C function ttyname().

tzname

Retrieves the time conversion information from the tzname variable.

        POSIX::tzset();
        ($std, $dst) = POSIX::tzname();

tzset

This is identical to the C function tzset().

umask

This is identical to Perl's builtin umask() function.

uname

Get name of current operating system.

        ($sysname, $nodename, $release, $version, $machine ) = POSIX::uname();

ungetc

Use method IO::Handle::ungetc() instead.

unlink

This is identical to Perl's builtin unlink() function.

utime

This is identical to Perl's builtin utime() function.

vfprintf

vfprintf() is C-specific.

vprintf

vprintf() is C-specific.

vsprintf

vsprintf() is C-specific.

wait

This is identical to Perl's builtin wait() function.

waitpid

Wait for a child process to change state. This is identical to Perl's builtin waitpid() function.

        $pid = POSIX::waitpid( -1, &POSIX::WNOHANG );
        print "status = ", ($? / 256), "\n";

wcstombs

This is identical to the C function wcstombs().

wctomb

This is identical to the C function wctomb().

write

Write to a file. This uses file descriptors such as those obtained by calling POSIX::open.

        $fd = POSIX::open( "foo", &POSIX::O_WRONLY );
        $buf = "hello";
        $bytes = POSIX::write( $b, $buf, 5 );

Returns undef on failure.

---

CLASSES

---

POSIX::SigAction

new

Creates a new POSIX::SigAction object which corresponds to the 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 POSIX::SigSet object, it defaults to the empty set. The third parameter contains the sa_flags, it defaults to 0.

        $sigset = POSIX::SigSet->new(SIGINT, SIGQUIT);
        $sigaction = POSIX::SigAction->new( 'main::handler', $sigset, &POSIX::SA_NOCLDSTOP );

This POSIX::SigAction object should be used with the POSIX::sigaction() function.

---

POSIX::SigSet

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 );

addset

Add a signal to a SigSet object.

        $sigset->addset( &POSIX::SIGUSR2 );

Returns undef on failure.

delset

Remove a signal from the SigSet object.

        $sigset->delset( &POSIX::SIGUSR2 );

Returns undef on failure.

emptyset

Initialize the SigSet object to be empty.

        $sigset->emptyset();

Returns undef on failure.

fillset

Initialize the SigSet object to include all signals.

        $sigset->fillset();

Returns undef on failure.

ismember

Tests the SigSet object to see if it contains a specific signal.

        if( $sigset->ismember( &POSIX::SIGUSR1 ) ){
                print "contains SIGUSR1\n";
        }

---

POSIX::Termios

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;

getattr

Get terminal control attributes.

Obtain the attributes for stdin.

        $termios->getattr()

Obtain the attributes for stdout.

        $termios->getattr( 1 )

Returns undef on failure.

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);

getcflag

Retrieve the c_cflag field of a termios object.

        $c_cflag = $termios->getcflag;

getiflag

Retrieve the c_iflag field of a termios object.

        $c_iflag = $termios->getiflag;

getispeed

Retrieve the input baud rate.

        $ispeed = $termios->getispeed;

getlflag

Retrieve the c_lflag field of a termios object.

        $c_lflag = $termios->getlflag;

getoflag

Retrieve the c_oflag field of a termios object.

        $c_oflag = $termios->getoflag;

getospeed

Retrieve the output baud rate.

        $ospeed = $termios->getospeed;

setattr

Set terminal control attributes.

Set attributes immediately for stdout.

        $termios->setattr( 1, &POSIX::TCSANOW );

Returns undef on failure.

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 );

setcflag

Set the c_cflag field of a termios object.

        $termios->setcflag( $c_cflag | &POSIX::CLOCAL );

setiflag

Set the c_iflag field of a termios object.

        $termios->setiflag( $c_iflag | &POSIX::BRKINT );

setispeed

Set the input baud rate.

        $termios->setispeed( &POSIX::B9600 );

Returns undef on failure.

setlflag

Set the c_lflag field of a termios object.

        $termios->setlflag( $c_lflag | &POSIX::ECHO );

setoflag

Set the c_oflag field of a termios object.

        $termios->setoflag( $c_oflag | &POSIX::OPOST );

setospeed

Set the output baud rate.

        $termios->setospeed( &POSIX::B9600 );

Returns undef on failure.

Baud rate values

B38400 B75 B200 B134 B300 B1800 B150 B0 B19200 B1200 B9600 B600 B4800 B50 B2400 B110

Terminal interface values

TCSADRAIN TCSANOW TCOON TCIOFLUSH TCOFLUSH TCION TCIFLUSH TCSAFLUSH TCIOFF TCOOFF

c_cc field values

VEOF VEOL VERASE VINTR VKILL VQUIT VSUSP VSTART VSTOP VMIN VTIME NCCS

c_cflag field values

CLOCAL CREAD CSIZE CS5 CS6 CS7 CS8 CSTOPB HUPCL PARENB PARODD

c_iflag field values

BRKINT ICRNL IGNBRK IGNCR IGNPAR INLCR INPCK ISTRIP IXOFF IXON PARMRK

c_lflag field values

ECHO ECHOE ECHOK ECHONL ICANON IEXTEN ISIG NOFLSH TOSTOP

c_oflag field values

OPOST

---

PATHNAME CONSTANTS

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

---

POSIX CONSTANTS

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

---

SYSTEM CONFIGURATION

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

---

ERRNO

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

---

FCNTL

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

---

FLOAT

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

---

LIMITS

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

---

LOCALE

Constants

LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME

---

MATH

Constants

HUGE_VAL

---

SIGNAL

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

---

STAT

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

Macros

S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISREG

---

STDLIB

Constants

EXIT_FAILURE EXIT_SUCCESS MB_CUR_MAX RAND_MAX

---

STDIO

Constants

BUFSIZ EOF FILENAME_MAX L_ctermid L_cuserid L_tmpname TMP_MAX

---

TIME

Constants

CLK_TCK CLOCKS_PER_SEC

---

UNISTD

Constants

R_OK SEEK_CUR SEEK_END SEEK_SET STDIN_FILENO STDOUT_FILENO STRERR_FILENO W_OK X_OK

---

WAIT

Constants

WNOHANG WUNTRACED

Macros

WIFEXITED WEXITSTATUS WIFSIGNALED WTERMSIG WIFSTOPPED WSTOPSIG

---

CREATION

This document generated by ./mkposixman.PL version 19960129.

---

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We are painfully aware that these documents may contain incorrect links and misformatted HTML. Such bugs lie in the automatic translation process that automatically created the hundreds and hundreds of separate documents that you find here. Please do not report link or formatting bugs, because we cannot fix per-document problems. The only bug reports that will help us are those that supply working patches to the installhtml or pod2html programs, or to the Pod::HTML module itself, for which I and the entire Perl community will shower you with thanks and praises.

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--Tom Christiansen, Perl Documentation Compiler and Editor

---

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