Alphabetical Listing of Perl Functions/ Perl Functions by Category

-X

run a file test

abs

absolute value function

accept

accept an incoming socket connect

alarm

schedule a SIGALRM

atan2

arctangent of Y/X

bind

binds an address to a socket

binmode

prepare binary files on old systems

bless

create an object

caller

get context of the current subroutine call

chdir

change your current working directory

chmod

changes the permissions on a list of files

chomp

remove a trailing record separator from a string

chop

remove the last character from a string

chown

change the owership on a list of files

chr

get character this number represents

chroot

make directory new root for path lookups

close

close file (or pipe or socket) handle

closedir

close directory handle

connect

connect to a remove socket

continue

optional trailing block in a while or foreach

cos

cosine function

crypt

one-way passwd-style encryption

dbmclose

breaks binding on a tied dbm file

dbmopen

create binding on a tied dbm file

defined

test whether a value, variable, or function is defined

delete

deletes a value from a hash

die

raise an exception or bail out

do

turn a BLOCK into a TERM

dump

create an immediate core dump

each

retrieve the next key/value pair from a hash

endgrent

be done using group file

endhostent

be done using hosts file

endnetent

be done using networks file

endprotoent

be done using protocols file

endpwent

be done using passwd file

endservent

be done using services file

eof

test a filehandle for its end

eval

catch exceptions or compile code

exec

abandon this program to run another

exists

test whether a hash key is present

exit

terminate this program

exp

raise e to a power

fcntl

file control system all

fileno

return file descriptor from filehandle

flock

lock an entire file with an advisory lock

fork

create a new process just like this one

format

declare a picture format with use by the write() function

formline

internal function used for formats

getc

get the next character from the filehandle

getgrent

get next group record

getgrgid

get group record given group user ID

getgrnam

get group record given group name

gethostbyaddr

get host record given its address

gethostbyname

get host record given name

gethostent

get next hosts record

getlogin

return who logged in at this tty

getnetbyaddr

get network record given its address

getnetbyname

get networks record given name

getnetent

get next networks record

getpeername

find the other hend of a socket connection

getpgrp

get process group

getppid

get parent process ID

getpriority

get current nice value

getprotobyname

get protocol record given name

getprotobynumber

get protocol record numeric protocol

getprotoent

get next protocols record

getpwent

get next passwd record

getpwnam

get passwd record given user login name

getpwuid

get passwd record given user ID

getservbyname

get services record given its name

getservbyport

get services record given numeric port

getservent

get next services record

getsockname

retrieve the sockaddr for a given socket

getsockopt

get socket options on a given socket

glob

expand filenames using wildcards

gmtime

convert UNIX time into record or string using Greenwich time

goto

create spaghetti code

grep

locate elements in a list test true against a given criterion

hex

convert a string to a hexadecimal number

import

patch a module's namespace into your own

int

get the integer portion of a number

ioctl

system-dependent device control system call

join

join a list into a string using a separator

keys

retrieve list of indices from a hash

kill

send a signal to a process or process group

last

exit a block prematurely

lc

return lower-case version of a string

lcfirst

return a string with just the next letter in lower case

length

return the number of bytes in a string

link

create a hard link in the filesytem

listen

register your socket as a server

local

create a temporary value for a global variable (dynamic scoping)

localtime

convert UNIX time into record or string using local time

log

retrieve the natural logarithm for a number

lstat

stat a symbolic link

m//

match a string with a regular expression pattern

map

apply a change to a list to get back a new list with the changes

mkdir

create a directory

msgctl

SysV IPC message control operations

msgget

get SysV IPC message queue

msgrcv

receive a SysV IPC message from a message queue

msgsnd

send a SysV IPC message to a message queue

my

declare and assign a local variable (lexical scoping)

next

iterate a block prematurely

no

unimport some module symbols or semantics at compile time

oct

convert a string to an octal number

open

open a file, pipe, or descriptor

opendir

open a directory

ord

find a character's numeric representation

pack

convert a list into a binary representation

package

declare a separate global namespace

pipe

open a pair of connected filehandles

pop

remove the last element from an array and return it

pos

find or set the offset for the last/next m//g search

print

output a list to a filehandle

printf

output a formatted list to a filehandle

prototype

get the prototype (if any) of a subroutine

push

append one or more elements to an array

q/STRING/

singly quote a string

qq/STRING/

doubly quote a string

quotemeta

quote regular expression magic characters

qw/STRING/

quote a list of words

qx/STRING/

backquote quote a string

rand

retrieve the next pseudorandom number

read

fixed-length buffered input from a filehandle

readdir

get a directory from a directory handle

readlink

determine where a symbolic link is pointing

recv

receive a message over a Socket

redo

start this loop iteration over again

ref

find out the type of thing being referenced

rename

change a filename

require

load in external functions from a library at runtime

reset

clear all variables of a given name

return

get out of a function early

reverse

flip a string or a list

rewinddir

reset directory handle

rindex

right-to-left substring search

rmdir

remove a directory

s///

replace a pattern with a string

scalar

force a scalar context

seek

reposition file pointer for random-access I/O

seekdir

reposition directory pointer

select

reset default output or do I/O multiplexing

semctl

SysV semaphore control operations

semget

get set of SysV semaphores

semop

SysV semaphore operations

send

send a message over a socket

setgrent

prepare group file for use

sethostent

prepare hosts file for use

setnetent

prepare networks file for use

setpgrp

set the process group of a process

setpriority

set a process's nice value

setprotoent

prepare protocols file for use

setpwent

prepare passwd file for use

setservent

prepare services file for use

setsockopt

set some socket options

shift

remove the first element of an array, and return it

shmctl

SysV shared memory operations

shmget

get SysV shared memory segment identifier

shmread

read SysV shared memory

shmwrite

write SysV shared memory

shutdown

close down just half of a socket connection

sin

return the sin of a number

sleep

block for some number of seconds

socket

create a socket

socketpair

create a pair of sockets

sort

sort a list of values

splice

add or remove elements anywhere in an array

split

split up a string using a regexp delimiter

sprintf

formatted print into a string

sqrt

square root function

srand

seed the random number generator

stat

get a file's status information

study

optimize input data for repeated searches

sub

declare a subroutine, possibly anonymously

substr

get or alter a portion of a stirng

symlink

create a symbolic link to a file

syscall()

execute an arbitrary system call

sysread

fixed-length unbuffered input from a filehandle

system

run a separate program

syswrite

fixed-length unbuffered output to a filehandle

tell

get current seekpointer on a filehandle

telldir

get current seekpointer on a directory handle

tie

bind a variable to an object class

time

return number of seconds since 1970

times

return elapsed time for self and child processes

tr///

transliterate a string

truncate

shorten a file

uc

return upper-case version of a string

ucfirst

return a string with just the next letter in upper case

umask

set file creation mode mask

undef

remove a variable or function definition

unlink

remove one link to a file

unpack

convert binary structure into normal perl variables

unshift

prepend more elements to the beginning of a list

untie

break a tie binding to a variable

use

load in a module at compile time

utime

set a file's last access and modify times

values

return a list of the values in a hash

vec

test or set particular bits in a string

wait()

wait for any child process to die

waitpid()

wait for a particular child process to die

wantarray

get list vs array context of current subroutine call

warn

print debugging info

write

print a picture record

y///

transliterate a string