Searching files in Linux with the find command

Searching files in Linux from the command line is easy using the find command. This Linux command uses a simple conditional mechanism to filter objects. Let’s see how to use the find command in Linux to locate a file from the command line.

Linux find command

The find command is used to locate files in Linux, based on user-specified criteria. The basic syntax of the command is as follows:

find -options /path expression

Find command attributes

• -options: options or search parameters enable control of the behavior and optimization method of the find process.
• /path: it defines the top-level directory where the find command will start filtering.
• expression: it defines the actions to perform to create an output.

Find command options

Locating files by name in Linux

For finding files by name in a directory and all sub-directories, type the following command into the command line:

find /path -name filename

Locating files by extension

For finding files by extension in a directory and all sub-directories, type the following command into the command line:

find /path -name *.html

Locating files in the current directory

For finding files in the current directory, type the following command into the command line:

find . -name filename.html

Locating files modified during a period of time

For finding files that have been changed during the previous week, type the following command into the command line:

find /path -mtime 7 “.html”

Locating files modified during a period of time by a particular user

For finding files that have been changed during the previous week by a particular user, type the following command into the command line:

find /path -user username -mtime 7 “.html”

Limiting the search to a specific number of sub-directories

For limiting the search to a maximum amount of sub-directories, add the -maxdepth X option to the command:

find -maxdepth 3 /path -name *.html

Ignoring text case

For making a case insensitive search, add the -iname option to the command:

find /path -iname *.html

Searching files

For exclusively searching files, add the -type f option to the command:

find /path -type f -name “*.html”

Searching directories

For exclusively searching directories, add the -type d option to the command:

find /path -type d -name “*.html”

Following and showing symbolic links

Since the find command ignores symbolic links by default, add the -L option to the command to follow and show them:

find -L /path -name *.html

Locating files by file size

For finding bigger than 500MB files in a directory and all sub-directories, type the following command into the command line:

find /path -size +500M

Combining two conditions or filters

For instance, for filtering files ranging between 500MB and 1GB in a directory and all sub-directories, type the following command into the command line:

find /path -size +500M -and -size -1G

Filtering by at least one of the specified conditions

For instance, for filtering files by one of the indicated extensions in a directory and all sub-directories, type the following command into the command line:

find /path -name *.docx -or -name *.odt

Excluding the second condition

For instance, for excluding an extension from a search in a directory and all sub-directories, type the following command into the command line:

find /path -name *.docx -not -name *.odt

Option or search parameter	Usage
-name	Filtering files by name.
-iname	Making a case insensitive search by name to locate a file.
.	Searching in the current directory.
-type	Filtering files by type of file.
-user	Filtering files by user.
-mtime	Filtering files limiting the period of time of its modification.
-maxdepth	Limiting the search to a given amount of sub-directories.
-L	Including symbolic links in the search.
-size	Filtering by file size.
-and	Placed between two conditions to indicate that it is necessary to include both conditions.
-or	Placed between two conditions to indicate that it is necessary to filter by at least one of the conditions.
-not	Placed between two conditions to indicate that it is necessary to ignore the second condition.

Find command optimizations

There are three stages of optimization for enhancing filtering when using the find Linux command.

-O1: default

-O1 is the standard setting. It enables find to start filtering by filename before running any other test.

find -O1 /path -name "*.html"

-O2: filename and type of file

-O2 enables find to filter by filename and type of file before running more demanding filters.

find -O2 /path -name "*.html"

-O3: efficiency and likelihood of success

–O3 enables find to automatically reorder filters to prioritize efficiency and likelihood of success.

find -O3 /path -name "*.html"

Searches based on content: Find + Grep

The find Linux command only filters files based on filenames and metadata. Therefore, in order to search files based on their content, it is necessary to add the grep command to the command line:

find /path -type f -exec grep “content” ‘{}’ \; -print

• -exec: it is a command that enables the find command to execute a given task once per matched file.
• ‘{}’: curly braces are the placeholder for the matched results.
• \;: the -exec option is closed by an escape and a semicolon to avoid it can be interpreted by the shell.
• -print: it prints the results on the screen.