POSIX

Provides access to standard POSIX 1003.1 identifiers: functions, classes, and constants. Can be used to import one or multiple symbols: 

use POSIX; # import all symbols use POSIX qw(setsid); # import one symbol use POSIX qw(:errno_h :fcntl_h); # import sets of symbols


Functions listed as C-specific are not implemented.
_exit Identical to C function _exit(2)
abort Identical to C function abort(3)
abs Identical to Perl's abs function
access Determines accessibility of a file; returns undef on failure
acos Identical to C function acos(3)
alarm Identical to Perl's alarm function
asctime Identical to C function asctime(3)
asin Identical to C function asin(3)
assert Similar to C macro assert(3)
atan Identical to C function atan(3)
atan2 Identical to Perl's atan2 function
atexit C-specific; use END {}
atof C-specific
atoi C-specific
atol C-specific
bsearch Not supplied
calloc C-specific
ceil Identical to C function ceil(3)
chdir Identical to Perl's chdir function
chmod Identical to Perl's chmod function
chown Identical to Perl's chown function
clearerr Uses method FileHandle::clearerr
clock Identical to C function clock(3)
close Closes a file; returns undef on failure
closedir Identical to Perl's closedir function
cos Identical to Perl's cos function
cosh Identical to C function cosh(3)
creat Creates a new file
ctermid Generates path name for the controlling terminal
ctime Identical to C function ctime(3)
cuserid Gets user's login name
difftime Identical to C function difftime(3)
div C-specific
dup Similar to C function dup(2); returns undef on failure
dup2 Similar to C function dup2(2); returns undef on failure
errno Returns the value of errno
execl C-specific; use Perl's exec
execle C-specific; use Perl's exec
execlp C-specific; use Perl's exec
execv C-specific; use Perl's exec
execve C-specific; use Perl's exec
execvp C-specific; use Perl's exec
exit Identical to Perl's exit function
exp Identical to Perl's exp function
fabs Identical to Perl's abs function
fclose Uses method FileHandle::close
fcntl Identical to Perl's fcntl function
fdopen Uses method FileHandle::new_from_fd
feof Uses method FileHandle::eof
ferror Uses method FileHandle::error
fflush Uses method FileHandle::flush
fgetc Uses method FileHandle::getc
fgetpos Uses method FileHandle::getpos
fgets Uses method FileHandle::gets
fileno Uses method FileHandle::fileno
floor Identical to C function floor(3)
fmod Identical to C function fmod(3)
fopen Uses method FileHandle::open
fork Identical to Perl's fork function
fpathconf Returns value of a configurable limit on a file or directory, or undef on failure
fprintf C-specific; use Perl's printf function
fputc C-specific; use Perl's print function
fputs C-specific; use Perl's print function
fread C-specific; use Perl's read function
free C-specific
freopen C-specific; use Perl's open function
frexp Returns mantissa and exponent of a floating-point number
fscanf C-specific; use <> and regular expressions
fseek Uses method FileHandle::seek
fsetpos Uses method FileHandle::setpos
fstat Gets file status
ftell Uses method FileHandle::tell
fwrite C-specific; use Perl's print function
getc Identical to Perl's etc function
getchar Returns one character from STDIN
getcwd Returns name of current working directory
getegid Returns effective group ID (gid)
getenv Returns value of the specified environment variable
geteuid Returns the effective user ID (uid)
getgid Returns the user's real group ID (gid)
getgrgid Identical to Perl's getgrgid function
getgrnam Identical to Perl's getgrnam function
getgroups Returns ids of the user's supplementary groups
getlogin Identical to Perl's getlogin function
getpgrp Identical to Perl's getpgrp function
getpid Returns ID of the process (pid)
getppid Identical to Perl's getppid function
getpwnam Identical to Perl's getpwnam function
getpwuid Identical to Perl's getpwuid function
gets Returns one line from STDIN
getuid Returns user's ID (uid)
gmtime Identical to Perl's gmtime function
isalnum Identical to C function, but can apply to one character or a whole string
isalpha Identical to C function, but can apply to one character or a whole string
isatty Returns Boolean indicating whether the specified filehandle is connected to a TTY
iscntrl Identical to C function, but can apply to one character or a whole string
isdigit Identical to C function, but can apply to one character or a whole string
isgraph Identical to C function, but can apply to one character or a whole string
islower Identical to C function, but can apply to one character or a whole string
isprint Identical to C function, but can apply to one character or a whole string
ispunct Identical to C function, but can apply to one character or a whole string
isspace Identical to C function, but can apply to one character or a whole string
isupper Identical to C function, but can apply to one character or a whole string
isxdigit Identical to C function, but can apply to one character or a whole string
kill Identical to Perl's kill function
labs C-specific; use Perl's abs function
ldexp Identical to C function ldexp(3)
ldiv C-specific; use division operator (/) and Perl's int function
link Identical to Perl's link function
localeconv Gets numeric formatting information. Returns reference to a hash containing the current locale formatting values.
localtime Identical to Perl's localtime function
log Identical to Perl's log function
log10 Identical to C function log10(3)
longjmp C-specific; use Perl's die function
lseek Moves the read/write file pointer; returns undef on failure
malloc C-specific
mblen Identical to C function mblen(3)
mbstowcs Identical to C function mbstowcs(3)
mbtowc Identical to C function mbtowc(3)
memchr C-specific; use Perl's index
memcmp C-specific; use eq
memcpy C-specific; use =
memmove C-specific; use =
memset C-specific; use x
mkdir Identical to Perl's mkdir function
mkfifo Similar to C function mkfifo(2); returns undef on failure
mktime Converts date/time information to a calendar time; returns undef on failure
modf Returns integral and fractional parts of a floating-point number
nice Similar to C function nice(3); returns undef on failure
offsetof C-specific
open Opens file for reading or writing; returns undef on failure
opendir Opens directory for reading; returns undef on failure
pathconf Retrieves value of a configurable limit on a file or directory; returns undef on failure
pause Similar to C function pause(3); returns undef on failure
perror Identical to C function perror(3)
pipe Creates an interprocess channel
pow Computes $x raised to the power $exponent
printf Prints specified arguments to STDOUT
putc C-specific; use Perl's print function
putchar C-specific; use Perl's print function
puts C-specific; use Perl's print function
qsort C-specific; use Perl's sort function
raise Sends specified signal to current process
rand Non-portable; use Perl's rand function
read Reads from a file; returns undef on failure
readdir Identical to Perl's readdir function
realloc C-specific
remove Identical to Perl's unlink function
rename Identical to Perl's rename function
rewind Seeks to beginning of file
rewinddir Identical to Perl's rewinddir function
rmdir Identical to Perl's rmdir function
scanf C-specific; use <> and regular expressions
setgid Sets real group id for this process
setjmp C-specific; use eval {}
setlocale Modifies and queries program's locale
setpgid Similar to C function setpgid(2); returns undef on failure
setsid Identical to C function setsid(8)
setuid Sets real user ID for this process
sigaction Detailed signal management; returns undef on failure
siglongjmp C-specific; use Perl's die function
sigpending Examines blocked, pending signals and returns undef on failure
sigprocmask Changes and/or examines this process's signal mask; returns undef on failure
sigsetjmp C-specific; use eval {}
sigsuspend Installs signal mask and suspends process until signal arrives; returns undef on failure
sin Identical to Perl's sin function
sinh Identical to C function sinh(3)
sleep Identical to Perl's sleep function
sprintf Identical to Perl's sprintf function
sqrt Identical to Perl's sqrt function
srand Identical to Perl's srand function
sscanf C-specific; use regular expressions
stat Identical to Perl's stat function
strcat C-specific; use .=
strchr C-specific; use index
strcmp C-specific; use eq
strcoll Identical to C function strcoll(3)
strcpy C-specific; use =
strcspn C-specific; use regular expressions
strerror Returns error string for the specified errno
strftime Converts date and time to string and returns the string
strlen C-specific; use length
strncat C-specific; use .= and/or substr
strncmp C-specific; use eq and/or substr
strncpy C-specific; use = and/or substr
stroul C-specific
strpbrk C-specific
strrchr C-specific; use rindex and/or substr
strspn C-specific
strstr Identical to Perl's index function
strtod C-specific
strtok C-specific
strtol C-specific
strtoul C-specific
strxfrm String transformation; returns the transformed string
sysconf Retrieves values of system configurable variables; returns undef on failure
system Identical to Perl's system function
tan Identical to C function tan(3)
tanh Identical to C function tanh(3)
tcdrain Similar to C function tcdrain(3); returns undef on failure
tcflow Similar to C function tcflow(3); returns undef on failure
tcflush Similar to C function tcflush(3); returns undef on failure
tcgetpgrp Identical to C function tcgetpgrp(3)
tcsendbreak Similar to C function tcsendbreak(3); returns undef on failure
tcsetpgrp Similar to C function tcsetpgrp(3); returns undef on failure
time Identical to Perl's time function
times Returns, in clock ticks, elapsed realtime since some point in the past, user and system times for this process, and user and system times for child processes
tmpfile Uses method FileHandle::new_tmpfile
tmpnam Returns a name for a temporary file
tolower Identical to Perl's lc function
toupper Identical to Perl's uc function
ttyname Identical to C function ttyname(3)
tzname Retrieves time conversion information from the tzname variable
tzset Identical to C function tzset(3)
umask Identical to Perl's umask function
uname Gets name of current operating system
ungetc Uses method FileHandle::ungetc
unlink Identical to Perl's unlink function
utime Identical to Perl's utime function
vfprintf C-specific
vprintf C-specific
vsprintf C-specific
wait Identical to Perl's wait function
waitpid Waits for child process to change state; identical to Perl's waitpid function
wcstombs Identical to C function wcstombs(3)
wctomb Identical to C function wctomb(3)
write Writes to file; returns undef on failure

The following sections show the classes that are defined and their methods:

POSIX::SigAction

POSIX::SigSet

POSIX::Termios

Constants

The following constants are associated with the Termios class:

The following are other constants defined in the POSIX module: