05-B.5: Searching for Files on Linux
- Page ID
- 32130
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2.3 Given a scenario, create, modify, and redirect files.
It is easy to forget where certain files are located, or perhaps the system, or another user/administrator created the file you need. No worries - Linux provides multiple tools to locate files on the system.
locate Command in Linux with Examples
The locate command in Linux is used to find the files by name. The locate utility works by searching through a database to find the file in question. This database contains bits and parts of files and their corresponding paths on your system. By default, the locate command does not check whether the files found in the database still exist and it will not report files created after the most recent update of the database.
Syntax:
locate [OPTION]... PATTERN...
Command Options:
| Option | Optoin Meaning |
|---|---|
| -b, –basename | Match only the base name against the specified patterns, which is the opposite of –wholename. |
| -c, –count | Instead of writing file names on standard output, write the number of matching entries only. |
| -d, –database DBPATH | Replace the default database with DBPATH. DBPATH is a (colon) separated list of database file names. If more than one –database option is specified, the resulting path is a concatenation of the separate paths. An empty database file name is replaced by the default database. A database file name – refers to the standard input. Note that a database can be read from the standard input only once. |
| -e, –existing | Print only entries that refer to files existing at the time locate is run. |
| -i, –ignore-case | Ignore case distinctions when matching patterns. |
| -n some number | Write matches up to the specified number. |
| -L, –follow | When checking whether files exist (if the –existing option is specified), follow trailing symbolic links. This causes broken symbolic links to be omitted from the output. This option is the default behavior. The opposite can be specified using –nofollow. |
| -h, –help | Write a summary of the available options to standard output and exit successfully. |
| -l, –limit, -n LIMIT | Exit successfully after finding LIMIT entries. If the –count option is specified, the resulting count is also limited to LIMIT. |
| -m, –mmap | Ignored, but included for compatibility with BSD and GNU locate. |
| -P, –nofollow, -H | When checking whether files exist (if the –existing option is specified), do not follow trailing symbolic links. This causes broken symbolic links to be reported like other files. This option is the opposite of –follow. |
| -0, –null | Separate the entries on output using the ASCII NUL character instead of writing each entry on a separate line. This option is designed for interoperability with the –null option of GNU xargs. |
| -S, –statistics | Write statistics about each read database to standard output instead of searching for files and exit successfully. |
| -q, –quiet | Write no messages about errors encountered while reading and processing databases. |
| -r, –regexp REGEXP | Search for a basic regexp REGEXP. No PATTERNs are allowed if this option is used, but this option can be specified multiple times. |
| –regex | Interpret all PATTERNs as extended regexps. |
| -s, –stdio | Ignored, for compatibility with BSD and GNU locate. |
| -V, –version | Write information about the version and license of locate on standard output and exit successfully. |
| -w, –wholename | Match only the whole path name against the specified patterns. This option is the default behavior. The opposite can be specified using –basename. |
The updatedb Command
The updatedb command creates or updates the database used by locate, and is usually run daily by cron to update the default database. If the database already exists, its data is reused to avoid rereading directories that have not changed. This command reads the /etc/updatedb.conf file, which contains directories that updatedb excludes from the database. The default location of the database is /etc/mlocate/mlocate.db.
Syntax:
updatedb [ OPTION ]
Command Options:
| Options | Option Meaning |
|---|---|
| -f, --add-prunefsFS | Add entries in white-space-separated list FS to PRUNEFS. |
| -n, --add-prunenamesNAMES | Add entries in white-space-separated list NAMES to PRUNENAMES. |
| -e, --add-prunepathsPATHS | Add entries in white-space-separated list PATHS to PRUNEPATHS. |
| -U, --database-root PATH | Store only results of scanning the file system subtree rooted at PATH to the generated database. The whole file system is scanned by default. |
| -o, --output FILE | Write the database to FILE instead of using the default database. |
| --prune-bind-mounts FLAG | Set PRUNE_BIND_MOUNTS to FLAG, overriding the configuration file. |
| --prunefs FS | Set PRUNEFS to FS, overriding the configuration file. |
| --prunenames NAMES | Set PRUNENAMES to NAMES, overriding the configuration file. |
| --prunepaths PATHS | Set PRUNEPATHS to PATHS, overriding the configuration file. |
| -l, --require-visibility FLAG | Set PRUNEPATHS to PATHS, overriding the configuration file. |
Adapted from
"locate command in Linux with Examples" by Pragya_Chaurasia, Geeks for Geeks is licensed under CC BY-SA 4.0