If you work within a disorganized workspace with deeply nested folders and try locating a specific folder, file or code snippet, then your productivity suffers from the constant distraction of manually searching through the workspace. Navigating the workspace and rummaging through every folder (double-clicking each one) to find a single folder or file becomes repetitive and directs attention away from your work. If you forget to close the folders after exploring them, then these opened folders accumulate over time and obstruct subsequent searches by cluttering the screen. Additionally, a computer's file explorer, such as Mac's Finder or Ubuntu's Nautilus, slows down when loading and displaying folders and files within large external hard-drives, thumb drives or SD cards filled (or nearly filled) to maximum capacity.

Operating systems based on the UNIX kernel provide the 

 command-line utilities to search for files/folders and text within a file respectively via pattern matching. With a single-line command, you avoid interacting with the interface of the computer's file explorer. Instead, the command prints the search results to standard output (

) displayed within the terminal. Both the 

 commands are considered as some of the most essential building blocks in bash scripting! Knowing how to use them allows you to integrate them into your continuous integration (CI) pipeline to automate search tasks.

 commands, we will search for directories and files within a downloaded copy of one of GitHub's most popular repositories, 

 command, as its name implies, recursively 

 directories and files located within a specified list of directory paths. When a file or directory matches search criteria (based on the options provided to the 

 command outputs the matched directories and files by their path relative to the given starting point/s.

To recursively list all of the directories and files (including those hidden) within the current directory:

To narrow our list down to a specific directory or file, we must provide an 

: Angle brackets indicate required arguments, whereas square brackets indicate optional arguments.

An expression describes how to identify a match via 

, which use certain properties of directories/files to determine which directory/file satisfies the defined conditions:

For more information on other tests, check out the 

To get started, let's search for all files named 

: This command also searches for all directories named 

. It is highly unlikely for directory names to contain extensions. To limit the search to files only, add the 

If we try to search for directories or files that do not exist, then 

 returns an empty list with an exit code of zero.

If you execute this command without the quotation marks around the glob pattern, then you may expect the terminal to also print a list of JSON files. However, notice that the terminal only prints a list of 

 file in the root of the current directory to 

 command, then notice that the terminal only prints this 

Without the quotation marks, Bash expands the glob pattern and will replace it with the first file in the current directory that matches this pattern, which is 

. To ensure that Bash does not expand the glob pattern and behave non-deterministically, wrap the glob pattern in quotation marks. Now, revert the renaming of 

Currently, this project has no empty directories:

When we search for empty directories within this project, the terminal will print the 

 to indicate the current directory, the argument passed to the 

 to allow the glob pattern to match the leading segment of a relative path.

 and forgot to add these prefixes to the glob pattern, then the 

$ find . -path "./packages/*/package.json"

 test filters out directories/files based on what the user is looking for. If the user only wants the 

 command to limit its search to files, then the 

The following command prints all of the files within the current directory.

 command to limit its search to directories, then the 

The following command prints all of the sub-directories within the current directory.

To search for multiple types, join the types together and separate each type with a comma.

Proceed on to the second part of this blog post, which dives into the 

<h1 data-node-type="titlePlaceholder" class="titlePlaceholder">Searching with <code>find</code> and <code>grep</code></h1><p>If you work within a disorganized workspace with deeply nested folders and try locating a specific folder, file or code snippet, then your productivity suffers from the constant distraction of manually searching through the workspace. Navigating the workspace and rummaging through every folder (double-clicking each one) to find a single folder or file becomes repetitive and directs attention away from your work. If you forget to close the folders after exploring them, then these opened folders accumulate over time and obstruct subsequent searches by cluttering the screen. Additionally, a computer's file explorer, such as Mac's Finder or Ubuntu's Nautilus, slows down when loading and displaying folders and files within large external hard-drives, thumb drives or SD cards filled (or nearly filled) to maximum capacity.</p><p>Operating systems based on the UNIX kernel provide the <code><a href="https://man7.org/linux/man-pages/man1/find.1.html" rel="noopener noreferrer nofollow">find</a></code> and <code><a href="https://man7.org/linux/man-pages/man1/grep.1.html" rel="noopener noreferrer nofollow">grep</a></code> command-line utilities to search for files/folders and text within a file respectively via pattern matching. With a single-line command, you avoid interacting with the interface of the computer's file explorer. Instead, the command prints the search results to standard output (<code>stdout</code>) displayed within the terminal. Both the <code>find</code> and <code>grep</code> commands are considered as some of the most essential building blocks in bash scripting! Knowing how to use them allows you to integrate them into your continuous integration (CI) pipeline to automate search tasks.</p><p>Below, I'm going to show you:</p><ul><li><p>How to locate folders and files via the <code>find</code> command within a folder hierarchy.</p></li><li><p>How to locate a text string via the <code>grep</code> command within a file.</p></li><li><p>How to interpret and construct your own glob patterns.</p></li></ul><p>To demonstrate the <code>find</code> and <code>grep</code> commands, we will search for directories and files within a downloaded copy of one of GitHub's most popular repositories, <a href="https://github.com/facebook/react" rel="noopener noreferrer nofollow">facebook/react</a>.</p><h2 class="heading-anchor-text" id="the-find-command"><span>The <code>find</code> Command</span><a class="d-inline" href="#the-find-command">#</a></h2><p>The <strong><code><a href="https://man7.org/linux/man-pages/man1/find.1.html" rel="noopener noreferrer nofollow">find</a></code></strong> command, as its name implies, recursively <em>finds</em> directories and files located within a specified list of directory paths. When a file or directory matches search criteria (based on the options provided to the <code>find</code> command), the <code>find</code> command outputs the matched directories and files by their path relative to the given starting point/s.</p><p>To recursively list all of the directories and files (including those hidden) within the current directory:</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-CX0gTtUyfAYbscBPj2qRd" id="cm-CX0gTtUyfAYbscBPj2qRd">$ find .</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/5azmifjiuzyfsky/Screen%20Shot%202021-03-21%20at%201.05.00%20PM.png" alt="Listing of All Directories and Files" contenteditable="false"><div></div></figure><p>To narrow our list down to a specific directory or file, we must provide an <strong>expression</strong> to the <code>find</code> command:</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-_imNoYbW4J11EfAiuNM0m" id="cm-_imNoYbW4J11EfAiuNM0m">$ find &lt;starting-point&gt; [expression]</textarea><p><em>Note</em>: Angle brackets indicate required arguments, whereas square brackets indicate optional arguments.</p><p>An expression describes how to identify a match via <strong>tests</strong>, which use certain properties of directories/files to determine which directory/file satisfies the defined conditions:</p><ul><li><p><strong>Name</strong> (<code>-name</code>) - Match if the name of a directory/file equals the name (a glob pattern) passed as the argument specified for <code>-name</code>. This test is case-sensitive. Use <code>-iname</code> for the case-insensitive variant.</p></li><li><p><strong>Empty</strong> (<code>-empty</code>) - Match if a directory is empty or a file has no content.</p></li><li><p><strong>Path</strong> (<code>-path</code>) - Match if a directory/file belongs within the path (a glob pattern) passed as the argument specified for <code>-path</code>. This test is case-sensitive. Use <code>-ipath</code> for the case-insensitive variant.</p></li><li><p><strong>Permissions</strong> (<code>-perm</code>) - Match if the permissions (read/write/execute for owner/group/everyone) of a directory/file equals the argument specified for <code>-perm</code>. <code>000</code> indicates no permissions, and <code>777</code> indicates full permissions. </p></li><li><p><strong>Regular Expression</strong> (<code>-regex</code>) - Match if the path of a directory/file fulfills the regular expression passed as the argument specified for <code>-regex</code>. This test is case-sensitive. Use <code>-iregex</code> for the case-insensitive variant.</p></li><li><p><strong>Size</strong> (<code>-size</code>) - Match if the size of a directory/file is greater than (<code>+</code> prefix), less than (<code>-</code> prefix) or equal (no prefix) to the argument specified for <code>-size</code>.</p></li><li><p><strong>Type</strong> (<code>-type</code>) - Match for a specific type. There are many supported types, but for this blog post, we are concerned with only directories (<code>d</code>) and files (<code>f</code>).</p></li></ul><p>For more information on other tests, check out the <code>find</code> command's <a href="https://man7.org/linux/man-pages/man1/find.1.html" rel="noopener noreferrer nofollow">documentation</a> in the Linux Manual Page.</p><h3 class="heading-anchor-text" id="name-name-test"><span>Name (<code>-name</code> Test)</span><a class="d-inline" href="#name-name-test">#</a></h3><p>To get started, let's search for all files named <code>package.json</code>.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-hNDQHFA1XE7xMTjAG6NOt" id="cm-hNDQHFA1XE7xMTjAG6NOt">$ find . -name "package.json"</textarea><p><em>Note</em>: This command also searches for all directories named <code>package.json</code>. It is highly unlikely for directory names to contain extensions. To limit the search to files only, add the <code>-type f</code> test.</p><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/uq4eck37soffuz4/Screen%20Shot%202021-03-21%20at%206.26.07%20PM.png" contenteditable="false"><div></div></figure><p>If we try to search for directories or files that do not exist, then <code>find</code> returns an empty list with an exit code of zero.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-JSpOAxKEPF19ajEXlzXvx" id="cm-JSpOAxKEPF19ajEXlzXvx">$ find . -name "package-x.json"</textarea><figure class="photo figure-position-inline"><img src="https://s3.amazonaws.com/assets.fullstack.io/n/20210322221141349_Screen%20Shot%202021-03-21%20at%206.24.52%20PM.png" attachmentid="1a4450f4-679f-4726-b88c-7a4eaa063c65" contenteditable="false" data-width="1260" data-height="48"><div></div></figure><p>Now let's search for all JSON files.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-yijsPFy5B73mEniT1lnu3" id="cm-yijsPFy5B73mEniT1lnu3">$ find . -name "*.json"</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/n6uhu7jvpsu32z5/Screen%20Shot%202021-03-21%20at%206.05.14%20PM.png" contenteditable="false"><div></div></figure><p>If you execute this command without the quotation marks around the glob pattern, then you may expect the terminal to also print a list of JSON files. However, notice that the terminal only prints a list of <code>package.json</code> files.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-8VYbE4tXF5KYvkM6FfyA9" id="cm-8VYbE4tXF5KYvkM6FfyA9">$ find . -name *.json</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/gn30xszo0mi3qmd/Screen%20Shot%202021-03-21%20at%206.04.19%20PM.png" contenteditable="false"><div></div></figure><p>Suppose we rename the <code>package.json</code> file in the root of the current directory to <code>package-x.json</code>. </p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-wyWi43fkpEUEzC88VJata" id="cm-wyWi43fkpEUEzC88VJata">$ mv package.json package-x.json</textarea><p>If we execute the previous <code>find</code> command, then notice that the terminal only prints this <code>package-x.json</code> file.</p><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/t3tf6iigw15wj2z/Screen%20Shot%202021-03-22%20at%2012.34.25%20AM.png" contenteditable="false"><div></div></figure><p>Without the quotation marks, Bash expands the glob pattern and will replace it with the first file in the current directory that matches this pattern, which is <code>package-x.json</code>. To ensure that Bash does not expand the glob pattern and behave non-deterministically, wrap the glob pattern in quotation marks. Now, revert the renaming of <code>package-x.json</code> back to <code>package.json</code>.</p><h3 class="heading-anchor-text" id="empty-empty-test"><span>Empty (<code>-empty</code> Test)</span><a class="d-inline" href="#empty-empty-test">#</a></h3><p>Currently, this project has no empty directories:</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm--0WYu5mGSiMKy2YQ4BKvv" id="cm--0WYu5mGSiMKy2YQ4BKvv">$ find . -empty</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/tttxchi62dlvj79/Screen%20Shot%202021-03-22%20at%2012.56.23%20AM.png" contenteditable="false"><div></div></figure><p>Let's create an empty directory:</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-L43sEdxHmfGEk-Lh44bIL" id="cm-L43sEdxHmfGEk-Lh44bIL">$ mkdir empty-dir</textarea><p>When we search for empty directories within this project, the terminal will print the <code>empty-dir</code> directory.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-g-8jZSrK006Hp7L7S2_Z3" id="cm-g-8jZSrK006Hp7L7S2_Z3">$ find . -empty</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/sc8icettc3uvx7f/Screen%20Shot%202021-03-22%20at%2012.58.06%20AM.png" contenteditable="false"><div></div></figure><h3 class="heading-anchor-text" id="path-path-test"><span>Path (<code>-path</code> Test)</span><a class="d-inline" href="#path-path-test">#</a></h3><p>Since relative paths start with <code>./</code> to indicate the current directory, the argument passed to the <code>-path</code> test must begin with either <code>*</code> or <code>./</code> to allow the glob pattern to match the leading segment of a relative path.</p><p>If we tried to locate <code>package.json</code> files with <code>-path</code> and forgot to add these prefixes to the glob pattern, then the <code>find</code> command returns an empty list.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-LhpQibBFNAYvnFtJKwwlq" id="cm-LhpQibBFNAYvnFtJKwwlq">$ find . -path "package.json"</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/lko5lbq9bastfxn/Screen%20Shot%202021-03-22%20at%201.14.49%20AM.png" contenteditable="false"><div></div></figure><p>Prepending <code>*</code> or <code>./</code> to the glob pattern allows the <code>find</code> command to correctly match for <code>package.json</code> files via their relative paths.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-97gCuxUeh3r9kyDHHT2Nk" id="cm-97gCuxUeh3r9kyDHHT2Nk">$ find . -path "*package.json"</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/ybc4jcbijd1fwve/Screen%20Shot%202021-03-22%20at%201.16.43%20AM.png" contenteditable="false"><div></div></figure><p>Let's find all <code>package.json</code> files within the <code>packages</code> sub-directory:</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-mNocHpxT-GEfTPgwBjFoA" id="cm-mNocHpxT-GEfTPgwBjFoA">$ find . -path "./packages/*/package.json"</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/zns5posgi74d13q/Screen%20Shot%202021-03-22%20at%201.21.55%20AM.png" contenteditable="false"><div></div></figure><h3 class="heading-anchor-text" id="type-type-test"><span>Type (<code>-type</code> Test)</span><a class="d-inline" href="#type-type-test">#</a></h3><p>The <code>-type</code> test filters out directories/files based on what the user is looking for. If the user only wants the <code>find</code> command to limit its search to files, then the <code>-type</code> test must be passed <code>f</code> for "file."</p><p>The following command prints all of the files within the current directory.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-sBWrRO606Qk2n6uphB1ZY" id="cm-sBWrRO606Qk2n6uphB1ZY">$ find . -type f</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/z2u7v0ru0nmqi9p/Screen%20Shot%202021-03-22%20at%201.37.20%20AM.png" contenteditable="false"><div></div></figure><p>If the user only wants the <code>find</code> command to limit its search to directories, then the <code>-type</code> test must be passed <code>d</code> for "directory."</p><p>The following command prints all of the sub-directories within the current directory.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-xP68qOdVo0fB3PHkQZuIB" id="cm-xP68qOdVo0fB3PHkQZuIB">$ find . -type d</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/1qo94oep5f1umhk/Screen%20Shot%202021-03-22%20at%201.45.39%20AM.png" contenteditable="false"><div></div></figure><p>To search for multiple types, join the types together and separate each type with a comma.</p><textarea data-iscodemirror="true" data-mode="text/x-sh" data-uniqueid="cm-ECPicSYEaaDRtx56jwdGQ" id="cm-ECPicSYEaaDRtx56jwdGQ">$ find . -type f,d</textarea><figure class="photo figure-position-inline"><img src="https://www.dl.dropboxusercontent.com/s/fu6a0rcj3yarpx3/Screen%20Shot%202021-03-22%20at%201.53.38%20AM.png" contenteditable="false"><div></div></figure><p>The <code>-type</code> test supports additional types: </p><ul><li><p><code>b</code> for <strong>Block Special Files</strong><em>Examples</em>:</p><ul><li><p>Hard-Drive Partitions </p></li><li><p>Memory Devices (SD Cards, Flash Drives) </p></li></ul></li><li><p><code>c</code> for <strong>Character Special Files</strong><em>Examples</em>:</p><ul><li><p>Terminal File</p></li><li><p><code>NULL</code> File</p></li><li><p>System Console File</p></li><li><p>File Descriptor File </p></li></ul></li><li><p><code>p</code> for <strong>FIFO Special Files</strong> (<strong>Named Pipes</strong>) <em>Example</em>:</p><ul><li><p>Shared File Systems</p></li></ul></li><li><p><code>l</code> for <strong>Symbolic Link Files</strong></p></li><li><p><code>s</code> for <strong>UNIX Domain Socket Address Files</strong></p></li><li><p><code>D</code> for <strong>Solaris Door Files</strong> </p></li></ul><h2 class="heading-anchor-text" id="next-steps"><span>Next Steps</span><a class="d-inline" href="#next-steps">#</a></h2><p>Proceed on to the second part of this blog post, which dives into the <code>grep</code> command.</p><h2 class="heading-anchor-text" id="sources"><span>Sources</span><a class="d-inline" href="#sources">#</a></h2><ul><li><p><a href="https://man7.org/linux/man-pages/index.html" rel="noopener noreferrer nofollow">Linux Online Manual Pages</a></p></li><li><p><a href="https://www.ibm.com/support/knowledgecenter/en/SSLTBW_2.1.0/com.ibm.zos.v2r1.bpxb200/dasspe.htm" rel="noopener noreferrer nofollow">IBM Special Files Documentation</a></p></li></ul><p></p>

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