Perl Functions & Keywords : a summary

Here are Perl's functions (including things that look like functions, like some keywords and named operators). Some functions may appear in more than one place just because they can be categorize in more than one place.

SCALARs or strings Functions:

chomp, chop, chr, crypt, hex, index, lc, lcfirst, length, oct, ord, pack, q//, qq//, reverse, rindex, sprintf, substr, tr///, uc, ucfirst, y///

Regular expressions and pattern matching Functions

m//, pos, quotemeta, s///, split, study, qr//, tr///

Numeric functions

abs, atan2, cos, exp, hex, int, log, oct, rand, sin, sqrt, srand

Functions for real @ARRAYs

pop, push, shift, splice, unshift

Functions for list data

grep, join, map, qw//, reverse, sort, unpack

Functions for real %HASHes

delete, each, exists, keys, values

Input and output functions
binmode, close, closedir, dbmclose, dbmopen, die, eof, fileno, flock, format, getc, print, printf, read, readdir, rewinddir, say, seek, seekdir, select, syscall, sysread, sysseek, syswrite, tell, telldir, truncate, warn, write

Functions for fixed length data or records

pack, read, syscall, sysread, syswrite, unpack, vec

Functions for filehandles, files, or directories

-X, chdir, chmod, chown, chroot, fcntl, glob, ioctl, link, lstat, mkdir, open, opendir, readlink, rename, rmdir, stat, symlink, sysopen, umask, unlink, utime, mkpath


Miscellaneous functions

defined, dump, eval, formline, local, my, our, reset, scalar, state, undef, wantarray

Functions for processes and process groups
alarm, exec, fork, getpgrp, getppid, getpriority, kill, pipe, qx//, setpgrp, setpriority, sleep, system, times, wait, waitpid

Low-level socket functions

accept, bind, connect, getpeername, getsockname, getsockopt, listen, recv, send, setsockopt, shutdown, socket, socketpair

System V interprocess communication functions

msgctl, msgget, msgrcv, msgsnd, semctl, semget, semop, shmctl, shmget, shmread, shmwrite

Fetching user and group info

endgrent, endhostent, endnetent, endpwent, getgrent, getgrgid, getgrnam, getlogin, getpwent, getpwnam, getpwuid, setgrent, setpwent

Fetching network info

endprotoent, endservent, gethostbyaddr, gethostbyname, gethostent, getnetbyaddr, getnetbyname, getnetent, getprotobyname, getprotobynumber, getprotoent, getservbyname, getservbyport, getservent, sethostent, setnetent, setprotoent, setservent

Time-related functions

gmtime, localtime, time, times

Keywords related to the control flow of your Perl program
caller, continue, die, do, dump, eval, exit, goto, last, next, redo, return, sub, wantarray

Keywords related to switch
break, continue, given, when, default

(These are only available if you enable the "switch" feature. See feature and "Switch statements" in perlsyn.)

Keywords related to scoping
caller, import, local, my, our, state, package, use
(state is only available if the "state" feature is enabled. See feature.)
 
Keywords related to perl modules
do, import, no, package, require, use

Keywords related to classes and object-orientation
bless, dbmclose, dbmopen, package, ref, tie, tied, untie, use

Functions new in perl5

abs, bless, break, chomp, chr, continue, default, exists, formline, given, glob, import, lc, lcfirst, lock, map, my, no, our, prototype, qr//, qw//, qx//, readline, readpipe, ref, sub*, sysopen, tie, tied, uc, ucfirst, untie, use, when

* - sub was a keyword in perl4, but in perl5 it is an operator, which can be used in expressions.

Functions obsoleted in perl5

dbmclose, dbmopen

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