How to use Find Command in Linux with examples

Find Linux Files by Name or Extension

Use find from the command line to locate a specific file by name or extension. The following example searches for *.log files in the /home/username/ directory and all sub-directories:

Common Linux Find Commands and Syntax

find expressions take the following form:

  • The options attribute will control the behavior and optimization method of the find process.
  • The starting/path attribute will define the top level directory where find begins filtering.
  • The expression attribute controls the tests that search the directory hierarchy to produce output.

Consider the following example command:


This command enables the maximum optimization level (-O3) and allows find to follow symbolic links (-L). find searches the entire directory tree beneath /var/www/ for files that end with .php.

Basic Examples

Command Description
find . -name testfile.txt Find a file called testfile.txt in current and sub-directories.
find /home -name '*.jpg Find all .jpg files in the /home and sub-directories.
find . -type f -empty Find an empty file within the current directory.
find /home -user exampleuser -mtime 7 -iname ".db" Find all .db files (ignoring text case) modified in the last 7 days by a user named exampleuser.

Options and Optimization for Find

The default configuration for find will ignore symbolic links (shortcut files). If you want find to follow and return symbolic links, you can add the -L option to the command, as shown in the example above.

find optimizes its filtering strategy to increase performance. Three user-selectable optimization levels are specified as -O1-O2, and -O3. The -O1 optimization is the default and forces find to filter based on filename before running all other tests.

Optimization at the -O2 level prioritizes file name filters, as in -O1, and then runs all file-type filtering before proceeding with other more resource-intensive conditions. Level -O3 optimization allows find to perform the most severe optimization and reorders all tests based on their relative expense and the likelihood of their success.

Similar Article  How to work with Linux Cron and Crontab utilities
Command Description
-O1 (Default) filter based on file name first.
-O2 File name first, then file-type.
-O3 Allow find to automatically re-order the search based on efficient use of resources and likelihood. of success
-maxdepth X Search current directory as well as all sub-directories X levels deep.
-iname Search without regard for text case.
-not Return only results that do not match the test case.
-type f Search for files.
-type d Search for directories.

Find Files by Modification Time

The find command contains the ability to filter a directory hierarchy based on when the file was last modified:


The first command returns a list of all files in the entire file system that end with the characters conf and have been modified in the last 7 days. The second command filters exampleuser user’s home directory for files with names that end with the characters conf and have been modified in the previous 3 days.

Use Grep to Find Files Based on Content

The find command is only able to filter the directory hierarchy based on a file’s name and meta data. If you need to search based on the content of the file, use a tool like grep. Consider the following example:

This searches every object in the current directory hierarchy (.) that is a file (-type f) and then runs the command grep "example" for every file that satisfies the conditions. The files that match are printed on the screen (-print). The curly braces ({}) are a placeholder for the find match results. The {} are enclosed in single quotes (') to avoid handing grep a malformed file name. The -exec command is terminated with a semicolon (;), which should be escaped (\;) to avoid interpretation by the shell.

Before the implementation of the -exec option, this kind of command might have used the xargscommand to generate a similar output:

The -exec option runs commands against every object that matches the find expression. Consider the following example:


This filters every object in the current hierarchy (.) for files named file.conf and runs the chmod o+rcommand to modify file permissions of the find results.

The commands run with the -exec are executed in the root directory of the find process. Use -execdir to execute the specified command in the directory where the match resides. This may alleviate security concerns and produce more desirable performance for some operations.

The -exec or -execdir options run without further prompts. If you prefer to be prompted before action is taken, replace -exec with -ok or -execdir with -okdir.

How to Find and Delete Files in the Linux Command Line

Use this option with extreme caution.

Add the option -delete to the end of a match expression to delete all files that match. Use this option when you are certain that the results only match the files that you wish to delete.

In the following example, find locates all files in the hierarchy starting at the current directory and fully recursing into the directory tree. In this example, find will delete all files that end with the characters .bak:


 

   

I hope this was helpful and i appreciate if you would like, subscribe or share our posts. I it is just a click

clickhere

2 Comments
  • Noons
    July 7, 2017

    Good post! Always good to see “old” techniques being shown for the power they have.
    One thing I found a while ago is that in Aix and most flavours of Unix – not sure about Linux – it’s possible to do also:
    find . -name \*.sql
    to get all SQL scripts.
    Apparently, “escaping” the * behaves much as the single quotes around the string?

Leave a Comment

%d bloggers like this: