SliTaz Packages

Ftop is to files what top is to processes. The progress of all open files and file systems can be monitored. If run as a regular user, the set of open files will be limited to those in that user's processes (which is generally all that is of interest to the user). In any case, the selection of which files to display is possible through a wide assortment of options. As with top, the items are displayed in order from most to least active.

The interface extends beyond the traditional capabilities and expectations of console applications. For instance, ftop supports two output modes, full (using ncurses) and limited (simple plain text). The output mode can be specified at invocation, or changed dynamically as the program runs. Limited output mode is well suited for piping into other utilities (such as grep or sed) or simply for redirecting into a file. Full output mode is much more visually appealing and contains a few more features. Keyboard control and interaction is not limited to full output mode; it is also available in limited output mode.

As another unique usability feature, the command line options for ftop exactly match the run-time keyboard commands. In other words, the '-p' command line option can be used to specify a list of processes at invocation, and while ftop is running, 'p' can be pressed to modify the list. As another example, '-h' will show the help screen when ftop starts, or 'h' can be pressed at any time afterward to show the help screen. This commonality exists for every configuration option. And the current value for all options can be viewed at a glance in the options screen.

Finally, ftop can also be easily configured to display additional files that are not currently open by any local processes, and file system usage. If an NFS client is writing a file on a local export, that file may not be open by any local process, so the additional files feature is used to display those files. One or more file systems can be monitored if many files are being created, for instance while restoring from a backup or extracting a large archive.

Ftop has many more features than those described here. Detailed online help describes all available functionality, and provides examples of some of the interesting ways in which ftop can be used.

Ftop currently makes use of the entries for each process in /proc/PID/fdinfo/ to determine the file position and other details.