Perl built-in functions

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Computing: Programming: Perl: built-in functions

Alphabetical

A

• abs(arg) - returns absolute value of arg
• accept()
• alarm($seconds) - sends an alarm signal after $seconds seconds
• atan2($y,$x) - returns the arctangent of $y/$x

B

• bind()
• binmode(filehandle) - sets filehandle to be treated as binary
• bless()

C

• caller()
• chdir()
• chmod()
• chomp()
• chop()
• chown()
• chr()
• chroot()
• close()
• closedir()
• connect()
• cos()
• crypt()

D

• dbmclose()
• dbmopen()
• defined()
• delete()
• die()
• do subroutine
• dump()

E

• each()
• endgrent
• endhostent
• endnetent
• endprotoent
• endpwent
• endservent
• eof()
• eval()
• exec()
• exists($assoc($key)) - returns TRUE if $key exists within the hash $assoc. Doesn't work with dbm hashes.
• exit()
• exp()

F

• fcntl()
• fileno()
• flock()
• fork
• format
• formline()

G

• getc()
• getgrent
• getgrgid()
• getgrnam()
• gethostbyaddr()
• gethostbyname()
• gethostent
• getlogin
• getnetbyaddr()
• getnetbyname()
• getnetent
• getpeername()
• getpgrp()
• getppid
• getpriority()
• getprotobyname()
• getprotobynumber()
• getprotoent
• getpwent
• getpwnam()
• getpwuid()
• getserverbyname()
• getserverbyport()
• getservent
• getsockname()
• getsockopt()
• glob()
• gmtime()
• goto()
• grep()

H

• hex()

I

• index()
• int()
• ioctl()

J

• join()

K

• keys()
• kill()

L

• last()
• lc(string) - returns string in lowercase
• lcfirst(string) - returns string with first character lowercased
• length(string) - returns length (number of characters in) string
• link(oldfile,newfile) - creates newfile as a link to oldfile
• listen(socket,queuesize) - waits for incoming events on a socket
• local(variable list) - makes all variables in variable list local to the current subroutine
• localtime(number) - converts the binary time stored in number to a 9-element list and localizes it to the machine's timezone
• log(number) - returns the natural logarithm (i.e. log_e) of number
• lstat(fileHandle) - returns file statistics for the file opened with file handle fileHandle (does not de-reference symbolic links)

M

• m/pattern/gimosx - performs pattern-matching; other characters may be used as delimiters instead of "/". See Perl regex
• map(expr,list) - returns an array containing the output of expr(list item) for each item in list
• mkdir(name,mode) - creates a directory named name (can be relative or absolute filespec), with the file attributes in mode. See mkdir for related information.
• msgctl
• msgget
• msgrcv
• msgsnd
• my(variable list) - makes all variables in variable list local to the current {block}

N

• next
• no

O

• oct(expr) - converts string from octal to decimal (query: is expr a string? BCD? integer?)
• open(fileHandle,name) - opens a file named name and associates it with fileHandle
• opendir(dirHandle,name) - opens a directory named name and associates it with dirHandle
• ord(string) - returns the ASCII code of the first character in string, as an integer