Learning Perl, Second Edition

B.2. Standard Modules

The following is a list of all Perl pragmas and modules included with the current Perl distribution (Version 5.004). The classification of the modules is admittedly arbitrary.

Table B.1. General Programming: Miscellaneous

Module	Function
autouse	Defers loading of a module until it's used
constant	Creates compile-time constants
Benchmark	Checks and compares running times of code
Config	Accesses Perl configuration information
Env	Imports environment variables
English	Uses English or awk names for punctuation variables
FindBin	Finds path of currently executing program
Getopt::Long	Extended processing of command-line options
Getopt::Std	Processes single-character switches with switch clustering
lib	Manipulates @INC at compile-time
Shell	Runs shell commands transparently within Perl
strict	Restricts unsafe constructs
Symbol	Generates anonymous globs; qualifies variable names
subs	Predeclares subroutine names
vars	Predeclares global variable names

Table B.2. General Programming: Error Handling and Logging

Module	Function
Carp	Generates error messages
diagnostics	Forces verbose warning diagnostics
sigtrap	Enables stack backtrace on unexpected signals
Sys::Syslog	Perl interface to UNIX syslog (3) calls

Table B.3. General Programming: File Access and Handling

Module	Function
Cwd	Gets pathname of current working directory
DirHandle	Supplies object methods for directory handles
Fcntl	Loads the C Fcntl.h defines
File::Basename	Parses file specifications
File::CheckTree	Runs many tests on a collection of files
File::Copy ...