Finding files linux command line

Find Command in Linux (Find Files and Directories)

The find command is one of the most powerful tools in the Linux system administrators arsenal. It searches for files and directories in a directory hierarchy based on a user given expression and can perform user-specified action on each matched file.

You can use the find command to search for files and directories based on their permissions, type, date, ownership, size, and more. It can also be combined with other tools such as grep or sed .

find Command Syntax #

The general syntax for the find command is as follows:

find [options] [path. ] [expression] 

• The options attribute controls the treatment of the symbolic links, debugging options, and optimization method.
• The path. attribute defines the starting directory or directories where find will search the files.
• The expression attribute is made up of options, search patterns, and actions separated by operators.

To search for files in a directory, the user invoking the find command needs to have read permissions on that directory.

Let’s take a look at the following example:

• The option -L (options) tells the find command to follow symbolic links.
• The /var/www (path…) specifies the directory that will be searched.
• The (expression) -name «*.js tells find to search files ending with .js (JavaScript files).

Find Files by Name #

Finding files by name is probably the most common use of the find command. To find a file by its name, use the -name option followed by the name of the file you are searching for.

For example, to search for a file named document.pdf in the /home/linuxize directory, you would use the following command:

find /home/linuxize -type f -name document.pdf

To run a case-insensitive search, change the -name option with -iname :

find /home/linuxize -type f -iname document.pdf

The command above will match “Document.pdf”, “DOCUMENT.pdf” ..etc.

Find Files by Extension #

Searching for files by extension is the same as searching for files by name. For example, to find all files ending with .log.gz inside the /var/log/nginx directory, you would type:

find /var/log/nginx -type f -name '*.log.gz'

It is important to mention that you must either quote the pattern or escape the asterisk * symbol with backslash \ so that it doesn’t get interpreted by the shell when you use the wildcard character.

To find all files that don’t match the regex *.log.gz you can use the -not option. For example, to find all files that don’t end in *.log.gz you would use:

find /var/log/nginx -type f -not -name '*.log.gz'

Find Files by Type #

Sometimes you might need to search for specific file types such as regular files, directories, or symlinks. In Linux, everything is a file.

To search for files based on their type, use the -type option and one of the following descriptors to specify the file type:

• f : a regular file
• d : directory
• l : symbolic link
• c : character devices
• b : block devices
• p : named pipe (FIFO)
• s : socket

For instance, to find all directories in the current working directory , you would use:

The common example would be to recursively change the website file permissions to 644 and directory permissions to 755 using the chmod command:

find /var/www/my_website -type d -exec chmod 0755 <> \;find /var/www/my_website -type f -exec chmod 0644 <> \;

Find Files by Size #

To find files based on the file size, pass the -size parameter along with the size criteria. You can use the following suffixes to specify the file size:

• b : 512-byte blocks (default)
• c : bytes
• w : two-byte words
• k : Kilobytes
• M : Megabytes
• G : Gigabytes

The following command will find all files of exactly 1024 bytes inside the /tmp directory:

find /tmp -type f -size 1024c

The find command also allows you to search for files that are greater or less than a specified size.

In the following example, we search for all files less than 1MB inside the current working directory. Notice the minus — symbol before the size value:

If you want to search for files with a size greater than 1MB , then you need to use the plus + symbol:

You can even search for files within a size range. The following command will find all files between 1 and 2MB :

find . -type f -size +1M -size 21M

Find Files by Modification Date #

The find command can also search for files based on their last modification, access, or change time.

Same as when searching by size, use the plus and minus symbols for “greater than” or “less than”.

Let’s say that a few days ago, you modified one of the dovecot configuration files, but you forgot which one. You can easily filter all files under the /etc/dovecot/conf.d directory that ends with .conf and has been modified in the last five days:

find /etc/dovecot/conf.d -name "*.conf" -mtime 5

Here is another example of filtering files based on the modification date using the -daystart option. The command below will list all files in the /home directory that were modified 30 or more days ago:

find /home -mtime +30 -daystart

Find Files by Permissions #

The -perm option allows you to search for files based on the file permissions.

For example, to find all files with permissions of exactly 775 inside the /var/www/html directory, you would use:

You can prefix the numeric mode with minus — or slash / .

When slash / is used as the prefix, then at least one category (user, group, or others) must have at least the respective bits set for a file to match.

Consider the following example command:

The above command will match all the files with read permissions set for either user, group, or others.

If minus — is used as the prefix, then for the file to match, at least the specified bits must be set. The following command will search for files that have read and write permission for the owner and group and are readable by other users:

Find Files by Owner #

To find files owned by a particular user or group, use the -user and -group options.

For example, to search for all files and directories owned by the user linuxize , you would run:

Here is a real-world example. Let’s say you want to find all files owned by the user www-data and change the ownership of the matched files from www-data to nginx :

find / -user www-data -type f -exec chown nginx <> \;

Find and Delete Files #

To delete all matching files, append the -delete option to the end of the match expression.

Ensure you are using this option only when you are confident that the result matches the files you want to delete. It is always a good idea to print the matched files before using the -delete option.

For example, to delete all files ending with .temp from the /var/log/ , you would use:

find /var/log/ -name `*.temp` -delete

Use the -delete option with extreme caution. The find command is evaluated as an expression and if you add the -delete option first, the command will delete everything below the starting points you specified.

When it comes to directories, find can delete only empty directories, same as rmdir .

Conclusion #

We have shown you how to use the find command with various options and criteria.

This article should give you a fundamental understanding of how to locate files on your Linux systems. You may also visit the find man page and read about all other powerful options of the find command.

If you have any questions or remarks, please leave a comment below.

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How to Search for Files from the Linux Command Line

Zaira Hira

Searching for files is relatively easy when you are using a GUI. But in certain environments like GUI-less servers, you need to search for files using the command line.

There is a powerful command in Linux that helps you search for files and folders called find . In this article, we will discuss the find command with some examples.

What is the find command in Linux?

The find command lets you efficiently search for files, folders, and character and block devices.

Below is the basic syntax of the find command:

find /path/ -type f -name file-to-search 

• /path is the path where file is expected to be found. This is the starting point to search files. The path can also be / or . which represent root and current directory, respectively.
• -type represents the file descriptors. They can be any of the below:

f – Regular file such as text files, images and hidden files.

d – Directory. These are the folders under consideration.

l – Symbolic link. Symbolic links point to files and are similar to shortcuts.

c – Character devices. Files that are used to access character devices are called character device files. Drivers communicate with character devices by sending and receiving single characters (bytes, octets). Examples include keyboards, sound cards and mouse.

b – Block devices. Files that are used to access block devices are called block device files. Drivers communicate with block devices by sending and receiving entire blocks of data. Examples include USB, CD-ROM

Examples of the find command

Now we know the syntax of the find command, let’s look at some examples.

How to search files by name or extension

Suppose we need to find files that contain «style» in their name. We’ll use this command:

Now let’s say we want to find files with a particular extension like .html . We’ll modify the command like this:

How to search hidden files

Hidden files are represented by a dot in the beginning of the filename. They are normally hidden, but can be viewed with ls -a in the current directory.

We can modify the find command as shown below to search for hidden files.

How to search log files and configuration files

Log files usually have the extension .log , and we can find them like this:

Similarly, we can search for configuration files like this:

How to search other files by type

We can search for character block files by providing c to -type :

Similarly, device block files can be found by using b :

How to search directories

In the example below, we are finding the folders named lib . Note that we are using -type d .

💡 Tip: we can identify directories by looking at the d flag in the output of ls -lrt .

How to search files by size

An incredibly helpful use of the find command is to list files based on a particular size.

Let’s apply an example in my home directory.

find . -type f -name ".*" -mtime +10

Practical examples of find with bash scripts

We can combine find with rm or mv to create meaningful bash scripts that can be automated.

Let’s say we want to create a script that moves log files older than 7 days to a backup path. From there, it deletes log files older that older than 30 days. We can create a script and schedule it with cron . You can learn more about cron jobs here.

#!/bin/bash # Script to move from logs older than 7 days to backup logs path: /app/backup_logs/ESB0* # move ESB01 logs to backup find /logs/esb01/audit -name "*.tar.gz" -mtime +7 -exec mv <> app/backup_logs/ESB01/ \; # Remove logs from backup path after 30 days find /app/backup_logs/ESB01 -name "*.tar.gz" -mtime +30 -exec rm <> \; 

Note that we are using exec with find . Basically, exec executes the command provided ( mv and rm in our case). <> is the placeholder which holds the results of the command. Lastly, we provide the delimiter ; . As we do not want the shell to interpret the semicolon, we escape it with \ .

The shared script is very useful in archiving and removing logs.

Wrapping up

In this article, we have studied the find command in detail and learned how to search files by name, type, size and modification time.

I hope you found this tutorial helpful.

You can read my other posts here.

Resources: Banner images from Office illustrations by Storyset and Canva.

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