Library of Perl

 Create an abbreviation table from a list 
 Usage:
	%foo = ();
	&abbrev(*foo,LIST);
	...
	$long = $foo{$short};

This module is a "pure virtual base class"--it has nothing of its own.
It's just there to inherit from one of the various DBM packages.  It
prefers ndbm for compatibility reasons with Perl 4, then Berkeley DB (See
L), GDBM, SDBM (which is always there--it comes with Perl), and
finally ODBM.   This way old programs that used to use NDBM via dbmopen()
can still do so, but new ones can reorder @ISA:

    @AnyDBM_File::ISA = qw(DB_File GDBM_File NDBM_File);

Note, however, that an explicit use overrides the specified order:

    use GDBM_File;
    @AnyDBM_File::ISA = qw(DB_File GDBM_File NDBM_File);

will only find GDBM_File.

Having multiple DBM implementations makes it trivial to copy database formats:

    use POSIX; use NDBM_File; use DB_File;
    tie %newhash,  DB_File, $new_filename, O_CREAT|O_RDWR;
    tie %oldhash,  NDBM_File, $old_filename, 1, 0;
    %newhash = %oldhash;

 Usage:
 
     &assert('@x > @y');
     &assert('$var > 10', $var, $othervar, @various_info);
 
 That is, if the first expression evals false, we blow up.  The
 rest of the args, if any, are nice to know because they will
 be printed out by &panic, which is just the stack-backtrace
 routine shamelessly borrowed from the perl debugger.

Load functions only on demand

This function will split up your program into files that the AutoLoader module can handle. Normally only used to build autoloading Perl library modules, especially extensions (like POSIX). You should look at how they're built out for details.

The Benchmark module encapsulates a number of routines to help you figure out how long it takes to execute some code.

Warn or die of errors (from perspective of caller)

Run many filetest checks on a tree

Compare 8-bit scalar data according to the current locale

Access Perl configuration option

Get pathname of current working directory

Dynamically load C libraries into Perl code

Use nice English (or awk) names for ugly punctuation variables

Perl module that imports environment variables

Module to control namespace manipulations

Load the C Fcntl.h defines

Supply object methods for filehandles

Traverse a file tree

Traverse a directory structure depth-first

Basic and extended getopt(3) processing

Perl pragma to compute arithmetic in integer instead of double

Perl pragma to request less of something from the compiler

Generate a Makefile for Perl extension

Open a process for both reading and writing

Open a process for reading, writing, and error handling

Perl interface to IEEE 1003.1 namespace

Check a host for upness

Perl pragma to enable stack backtrace on unexpected signals

Load the C socket.h defines

Perl pragma to restrict unsafe constructs

Perl pragma to predeclare sub names