Filesys::DfPortable - Perl extension for filesystem disk space information.


  use Filesys::DfPortable;

  my $ref = dfportable("C:\\"); # Default block size is 1, which outputs bytes
  if(defined($ref)) {
     print"Total bytes: $ref->{blocks}\n";
     print"Total bytes free: $ref->{bfree}\n";
     print"Total bytes avail to me: $ref->{bavail}\n";
     print"Total bytes used: $ref->{bused}\n";
     print"Percent full: $ref->{per}\n"

  my $ref = dfportable("/tmp", 1024); # Display output in 1K blocks
  if(defined($ref)) {
     print"Total 1k blocks: $ref->{blocks}\n";
     print"Total 1k blocks free: $ref->{bfree}\n";
     print"Total 1k blocks avail to me: $ref->{bavail}\n";
     print"Total 1k blocks used: $ref->{bused}\n";
     print"Percent full: $ref->{per}\n"


This module provides a portable way to obtain filesystem disk space information.

The module should work with all versions of Windows (95 and up), and with all flavors of Unix that implement the statvfs or the statfs calls. This would include Linux, *BSD, HP-UX, AIX, Solaris, Mac OS X, Irix, Cygwin, etc ...

This module differs from Filesys::Df in that it has added support for Windows, but does not support open filehandles as a argument.

dfportable() requires a directory argument that represents the filesystem you want to query. There is also an optional block size argument so that you can tailor the size of the values returned. The default block size is 1, this will cause the function to return the values in bytes. If you never use the block size argument, then you can think of any instance of "blocks" in this document to really mean "bytes".

dfportable() returns a reference to a hash. The keys available in the hash are as follows:

{blocks} = Total blocks on the filesystem.

{bfree} = Total blocks free on the filesystem.

{bavail} = Total blocks available to the user executing the Perl application. This can be different than {bfree} if you have per-user quotas on the filesystem, or if the super user has a reserved amount. {bavail} can also be a negative value because of this. For instance if there is more space being used then you have available to you.

{bused} = Total blocks used on the filesystem.

{per} = Percent of disk space used. This is based on the disk space available to the user executing the application. In other words, if the filesystem has 10% of its space reserved for the superuser, then the percent used can go up to 110%.

You can obtain inode information through the module as well. But you must call exists() on the {files} key to make sure the information is available. Some filesystems may not return inode information, for example Windows, and some NFS filesystems.

Here are the available inode keys:

{files} = Total inodes on the filesystem.

{ffree} = Total inodes free on the filesystem.

{favail} = Total inodes available to the user executing the application. See the rules for the {bavail} key.

{fused} = Total inodes used on the filesystem.

{fper} = Percent of inodes used on the filesystem. See rules for the {per} key.

If the dfportable() call fails for any reason, it will return undef. This will probably happen if you do anything crazy like try to get information for /proc, or if you pass an invalid filesystem name, or if there is an internal error. dfportable() will croak() if you pass it a undefined value.

Requirements: Your system must contain statvfs(), statfs(), GetDiskFreeSpaceA(), or GetDiskFreeSpaceEx(). You must be running Perl 5.6 or higher.


Ian Guthrie

Copyright (c) 2006 Ian Guthrie. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


statvfs(2), statfs(2), df(1), GetDiskFreeSpaceA, GetDiskFreeSpaceEx, Filesys::Df