File::Random - Version 0.10 =========================== NAME File::Random - Perl module for random selecting of a file SYNOPSIS use File::Random qw/random_file/; my $fname = random_file(); my $fname2 = random_file(-dir => $dir); my $random_gif = random_file(-dir => $dir, -check => qr/\.gif$/, -recursive => 1); my $no_exe = random_file(-dir => $dir, -check => sub {! -x}); my @jokes_of_the_day = content_of_random_file(-dir => '/usr/lib/jokes'); my $joke_of_the_day = content_of_random_file(-dir => '/usr/lib/jokes'); my $word_of_the_day = random_line('/usr/share/dict/words'); DESCRIPTION This module simplifies the routine job of selecting a random file. (As you can find at CGI scripts). It's done, because it's boring (and errorprone), always to write something like my @files = (<*.*>); my $randf = $files[rand @files]; or opendir DIR, " ... " or die " ... "; my @files = grep {-f ...} (readdir DIR); closedir DIR; my $randf = $files[rand @files]; It also becomes very boring and very dangerous to write randomly selection for subdirectory searching with special check-routines. The simple standard job of selecting a random line from a file is implemented, too. FUNCTION random_file Returns a randomly selected file(name) from the specified directory If the directory is empty, undef will be returned. There 3 options: my $file = random_file( -dir => $dir, -check => qr/.../, # or sub { .... } -recursive => 1 # or 0 ); -dir Specifies the directory where file has to come from. Is the -dir option missing, a random file from the current directory will be used. That means '.' is the default for the -dir option. -check With the -check option you can either define a regex every filename has to follow, or a sub routine which gets the filename as argument. The filename includes the relative path (from the -dir directory or the current directory). Note, that -check doesn't accept anything else than a regexp or a subroutine. A string like '/.../' won't work. I still work on that. The default is no checking (undef). -recursive Enables, that subdirectories are scanned for files, too. Every file, independent from its position in the file tree, has the same chance to be choosen. Now the relative path from the given subdirectory or the current directory of the randomly choosen file is included to the file name. Every true value sets recursive behaviour on, every false value switches off. The default if false (undef). Note, that I programmed the recursive routine very defendly (using File::Find). So switching -recursive on, slowers the program a bit :-) FUNCTION content_of_random_file Returns the content of a randomly selected random file. In list context it returns an array of the lines of the selected file, in scalar context it returns a multiline string with whole the file. The lines aren't chomped. This function has the same parameter and a similar behaviour to the random_file method. Note, that -check still gets the filename and not the filecontent. FUNCTION random_line($filename) Returns a random_line from a (existing) file. If the file is empty, undef is returned. EXPORT None by default. You can export the function random_file with "use File::Random qw/random_file/;", "use File::Random qw/content_of_random_file/" or with the more simple "use File::Random qw/:all/;". I didn't want to pollute namespaces as I could imagine, users write methods random_file to create a file with random content. If you think I'm paranoid, please tell me, then I'll take it into the export. DEPENDENCIES This module requires these other modules and libraries: Test::More Test::Exception Test::Class Set::Scalar File::Temp Test::Class itselfs needs the following additional modules: Attribute::Handlers Class::ISA IO::File Storable Test::Builder Test::Builder::Tester Test::Differences All these modules are needed only for the tests. You can work with the module even without them. These modules are only needed for my test routines, not by the File::Random itself. (However, it's a good idea most to install most of the modules anyway). COPYRIGHT This Program is free software. You can change or redistribute it under the same condition as Perl itself. Copyright (c) 2002, Janek Schleicher, AUTHOR Janek Schleicher, SEE ALSO Tie::Pick Data::Random