++ed by:

2 non-PAUSE users.

Deven T. Corzine


Tie::FS - Read and write files using a tied hash


Version 0.1.0


  use Tie::FS;                       # Initialize Tie::FS module.

  tie %hash, Tie::FS, $flag, $dir;   # Ties %hash to files in $dir.

  @files = keys %hash;               # Retrieves directory list of $dir.

  $data = $hash{$file1};             # Reads "$dir/$file1" into $data.
  $hash{$file1} = $data;             # Writes $data into "$dir/$file1".
  $hash{$file2} = $hash{$file1};     # Copies $file1 to $file2.

  if (exists $hash{$path}) {...}     # Checks if $path exists at all.

  if (defined $hash{$path}) {...}    # Checks if $path is a file.

  $data = delete $hash{$file};       # Deletes $file, returns contents.

  undef %hash;                       # Deletes ALL regular files in $dir.


This module ties a hash to a directory in the filesystem. If no directory is specified in the $dir parameter, then "." (the current directory) is assumed. The $flag parameter defaults to the "Create" flag.

The following (case-insensitive) access flags are available:

  ReadOnly      Access is strictly read-only.
  Create        Files may be created but not overwritten or deleted.
  Overwrite     Files may be created, overwritten or deleted.
  ClearDir      Also allow files to be cleared (all deleted at once).

The pathname specified as a key to the hash may either be a relative path or an absolute path. For relative paths, the default directory specified to tie() will be prepended to the path.

The exists() function will be true if the specified path exists, including directories and non-regular files (such as symbolic links). Directories and non-regular files will return undef; only regular files will return a defined values. Empty regular files return "", not undef. Attempting to store undef in the tied will have no effect.

The keys() function will scan the directory (without sorting it), eliminate "." and ".." entries and append "/" for directories. (values() and each() will follow the same rules for selecting entries.) The following code will retrieve a sorted list of subdirectories:

  @subdirs = sort grep {s/\/$//} keys %hash;


Unless an absolute path was specified to tie(), a later chdir() will affect the paths accessed by the tied hash with relative paths.

A symbolic link is considered a non-regular file; it will not be followed unless a "/" follows the link name and the link points to a directory.

To perform a defined() test, the entire file must be read into memory, even if it will be discarded immediately after the test. The exists() function does not need to read the contents of a file.


Deven T. Corzine <deven@ties.org>


Please report any bugs or feature requests to bug-tie-fs at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Tie-FS.


You can find documentation for this module with the perldoc command.

    perldoc Tie::FS

You can also look for information at:


File::Slurp was the inspiration for this module, which is intended to provide similar functionality in a more "Perlish" way.


Copyright 2011 Deven T. Corzine.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.