locate command finds files by name. This command is fast because it has contents that is stored in the database. On regular basis locate runs a cron that updates the system. So instead of having search the entire system when you use locate. It is searching the database. Remember, the database must always be up-to-date if you want to find recently created files.
The database can be updated manually by typing the following command:
locate [OPTION]… PATTERN…
1.) This command locates files named hello on the system.
2.) This command locates files named pwd on the system.
locate pwd /etc/.pwd.lock /usr/bin/pwd /usr/bin/pwdx /usr/lib/modules/3.10.0-327.el7.x86_64/kernel/drivers/watchdog/hpwdt.ko /usr/lib/x86_64-redhat-linux6E/include/pwd.h /usr/lib64/cracklib_dict.pwd /usr/lib64/python2.7/site-packages/ldap/controls/pwdpolicy.py /usr/lib64/python2.7/site-packages/ldap/controls/pwdpolicy.pyc /usr/lib64/python2.7/site-packages/ldap/controls/pwdpolicy.pyo /usr/sbin/unix_chkpwd /usr/share/cracklib/cracklib-small.pwd /usr/share/cracklib/pw_dict.pwd /usr/share/doc/krb5-workstation-1.13.2/user/pwd_mgmt.html /usr/share/man/man0p/pwd.h.0p.gz /usr/share/man/man1/pwd.1.gz /usr/share/man/man1/pwdx.1.gz /usr/share/man/man1p/pwd.1p.gz /usr/share/man/man3/lckpwdf.3.gz /usr/share/man/man3/ulckpwdf.3.gz /usr/share/man/man8/unix_chkpwd.8.gz /usr/share/man/overrides/de/man1/pwdx.1 /usr/share/man/overrides/fr/man1/pwdx.1 /usr/share/man/overrides/uk/man1/pwdx.1
3.) -c option to locate, display the count of the number of matching entries.
locate -c pwd 24
Locate OPTIONS with Description as specified in man pages
This option matches only the base name against the specified pattern on the terminal. It is the opposite of –wholename.
-c option writes the number of matching entries instead of writing file names on standard output.
-d replaces the default database with DBPATH.
An empty database file name is replaced by the default database available. A database file name – refers to the standard input.
It displays only that entries which refer to files existing at a time when locate is run.
It displays a summary of the all available options to terminal output and then exits successfully.
-i ignore case distinctions when matching patterns.
It exits successfully once LIMIT entries are found.
Instead of searching for files. It writes statistics about each read database to standard output and then exits successfully.
Interpret all PATTERNs as extended regexps.
-V option write information about the license and version of locate on the terminal and then exits successfully.
-w matches only the whole path name with the specified pattern.
This behavior is the default. The opposite of it can be specified using –basename.