13.6. Locating Files and Directories
There will be times when you know a file or directory exists but you
will not know where to find it. Search for a file or directory with the
With locate, you will see every file or
directory whose name contains the search criterion. For example, if you want to
search for all files with the word finger in the name,
The locate command uses a database to locate
files and directories that have the word finger in
the file or directory name. The search results could include a file
called finger.txt, a file called
pointerfinger.txt, a directory named
fingerthumbnails, and so on. To learn more about
locate, read the locate man page
(type man locate at a shell prompt).
The locate command works very quickly, as long as
the database is up to date. That database is automatically updated on a
nightly basis through a cron
job. cron is a small program that runs in the
background, performing various tasks (such as updating the
locate database) at regularly scheduled intervals.
Cron is a
daemon that executes tasks at regularly scheduled
intervals. To read the cron man page, type
man cron at the shell prompt. Refer to the
Red Hat Linux Customization Guide for more information on
The cron task periodically updates the
slocate database, which is used to catalog file
locations. Switching between operating systems and shutting down your
machine at the end of the day can interfere with the automatic database
update run by cron.
To update the database manually, log in as root (type
su at a shell prompt and then your root password)
and type the command updatedb.
After a few minutes, the slocate database that
is used by the locate command will be current.
You can run anacron to have
your system execute commands periodically, with a frequency specified in
days. Unlike cron, it does not assume that the
machine is running continuously. Hence, it can be used on machines that
are not running 24 hours a day, to control daily, weekly, and monthly
jobs that are usually controlled by cron.
Refer to the man page on anacron (type
man anacron at the command line) and the
Red Hat Linux Customization Guide for more information.