The df command displays information about total space and available space on a file system. You can specify the name of a device on which the file system is located, the directory on which the file system is mounted, or the relative path name of the file system. You can also specify a file or directory that is not a mount point, and the df command displays information for the file system on which the file or directory is located. If you just specify the command with no parameters, it displays information for all currently mounted file systems. File system statistics are displayed in units of 512-byte blocks by default.

The df command gets file system space statistics from the statfs system call. However, when you specify the -s flag, you get the statistics from the virtual file system (VFS) specific file system helper. Under certain exceptional conditions, such as when a file system is being modified while the df command is running, the statistics displayed by the df command might not be accurate.

Note: Some remote file systems, such as the Network File System (NFS), do not provide all the information that the df command needs. The df command prints blanks for statistics that the server does not provide.

To display information about all mounted file systems, enter:


If your system has the /, /usr, /site, and/usr/venus systems mounted, the output from the df command resembles this:

Filesystem 512-blocks Free %Used Iused %Iused    Mounted on
/dev/hd0      19368   9976  48%   4714     5%    /
/dev/hd1      24212   4808  80%   5013    19%    /usr
/dev/hd2       9744   9352  4%    1900     4%    /site
/dev/hd3       3868   3856  0%    986      0%    /usr/venus