ff Command

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Purpose

Lists the file names and statistics for a file system.

Syntax

ff [ -a Number ] [ -c Number ] [ -I ] [ -l ] [ -m Number ] [ -n File ] [-o Options] [ -p Prefix ] [ -s ] [ -u ] [ -V VFSName ] [ -i I-Number [ ,I-Number ... ] ] [ FileSystem | DeviceName]

Description

The ff command reads the i-nodes in the file system specified by the FileSystem parameter and then writes information about them to standard output. It assumes the FileSystem is a file system, which is referenced in the /etc/filesystems file, and saves i-node data for files specified by flags.

The output from the ff command consists of the path name for each requested i-node number, in addition to other file information that you can request using the flags. The output is listed in order by i-node number, with tabs between all fields. The default line produced by the ff command includes the path name and i-node number fields. With all flags enabled, the output fields include path name, i-node number, size, and UID (user ID).

The Number parameter is a decimal number that specifies a number of days. It is prefixed by a + or - (plus or minus sign). Therefore, +3 means more than 3 days, -3 means less than 3 days, and 3 means 3 days, where a day is defined as a 24-hour period.

The ff command lists only a single path name out of many possible ones for an i-node with more than one link, unless you specify the -l flag. With the -l flag, the ff command lists all links.

Flags

Item Description
-a Number Displays the file if it has been accessed within the number of days specified by the Number parameter.
-c Number Displays the file if its i-node has been changed within the number of days specified by the Number parameter.
-i I-Number Displays the files corresponding to the i-node numbers specified by the I-Number parameter. The i-node numbers listed must be separated by a comma.
-I (This flag is an uppercase i.) Does not display the i-node after each path name.
Item Description
-l (This flag is a lowercase L.) Additionally displays a list of pathnames for files with more than one link.
-m Number Displays the file if it has been modified within the number of days specified by the Number parameter.
-n File Displays the file if it has been modified more recently than the file specified by the File parameter.
-o Options Specifies a comma-separated list of implementation-specific options for a virtual file system.

The following options are specific to the enhanced journaled file system (JFS2):

-o snapshot=snapName Specifies the name of the internal snapshot subject to the ff command. The file system owning the snapshot must be mounted.
-p Prefix Adds the prefix specified by the Prefix parameter to each path name. The default prefix is . (dot).
-s Writes the file size, in bytes, after each path name.
-u Writes the owner's login name after each path name.
-V VFSName Instructs the ff command to assume the file system is of type VFSName, overriding the value in the /etc/filesystems file.

Security

Attention RBAC users and Trusted AIX users: This command can perform privileged operations. Only privileged users can run privileged operations. For more information about authorizations and privileges, see Privileged Command Database in Security. For a list of privileges and the authorizations associated with this command, see the lssecattr command or the getcmdattr subcommand.

Examples

  1. To list the path names of all files in a given file system, enter:
    ff     -I    /dev/hd0
    This displays the path names of the files on the /dev/hd0 device. If you do not specify the -I flag, the ff command also displays the i-node number of each file.
  2. To list files that have been modified recently, enter:
    ff     -m    -2     -u    /dev/hd0
    This displays the path name, i-node number, and owner's user name (the -u flag) of each file on the /dev/hd0 device that has been modified within the last two days ( -m -2).
  3. To list files that have not been used recently, enter:
    ff     -a    +30    /dev/hd0
    This displays the path name and i-node of each file that was last accessed more than 30 days ago ( -a +30).
  4. To find out the paths corresponding to certain i-node numbers, enter:
    ff     -l     -i    451,76    /dev/hd0
    This displays all the path names (-l) associated with i-nodes 451 and 76.

Files

Item Description
/etc/vfs Contains descriptions of virtual file system types.
/etc/filesystems Lists the known file systems and defines their characteristics.