Complete Guide to File Search in Ubuntu | Using find, locate, grep, and GUI Tools

By 佐川 直弘 | Naohiro Sagawa (運営者)

※記事内に広告を含みます。Amazonアソシエイトとして適格販売により収入を得ています。　

1. Introduction

Ubuntu is a widely used Linux distribution, and mastering efficient file search methods is essential for improving daily workflow.
In this article, we will provide a clear explanation of the file search commands and tools available in Ubuntu, making it easy to understand for beginners and intermediate users alike.
We will also cover tips to improve search speed and troubleshooting methods, so be sure to check it out!

2. Basic File Search Commands

Ubuntu provides several basic commands for searching files.
In this section, we will explain key commands like find and locate.

2.1 What is the find Command?

The find command is a powerful tool that allows you to search for files in a specified directory based on filename or conditions.

Basic Syntax of the find Command

find [starting directory] [search conditions]

Example: Searching for a specific file named “example.txt” in the home directory

find ~/ -name "example.txt"

Common Options for the find Command

• -name: Search by filename (case-sensitive)
• -iname: Search by filename (case-insensitive)
• -type: Specify file type (d=directory, f=file)
• -size: Search by file size (e.g., +1M for files larger than 1MB)

2.2 What is the locate Command?

The locate command is known for its extremely fast search speed, but it relies on an index database.

Basic Syntax of the locate Command

locate [filename or part of the path]

Example: Searching for files containing “example” in their name

locate example

Important Notes on locate

Since locate uses a database, newly created files may not appear in search results. If this happens, update the database using the following command:

sudo updatedb

2.3 When to Use find and locate

• find: Best for detailed searches with specific conditions.
• locate: Best for quick searches.

3. Detailed Explanation of the find Command

The find command has extensive functionalities, allowing you to conduct efficient searches by using various options.
This section provides a detailed explanation with practical examples.

3.1 Searching by Filename

To search by filename, use the -name or -iname option.

Example: Searching for all files with the “.txt” extension

find ~/ -name "*.txt"

3.2 Searching by File Size

You can set search conditions based on file size.

Example: Searching for files larger than 1MB

find ~/ -size +1M

3.3 Searching by Modification Date

Using the -mtime option, you can search for files modified within a specified number of days.

Example: Searching for files modified within the last 7 days

find ~/ -mtime -7

3.4 Executing Actions on Search Results

You can also execute actions on the search results.

Example: Deleting all found files with the “.tmp” extension

find ~/ -name "*.tmp" -exec rm -f {} ;

4. Utilizing the locate Command

The locate command is not only easy to use but also operates at high speed.
This section introduces useful ways to utilize the locate command.

4.1 Searching by Partial Path

Even if you don’t know the exact filename, you can search using part of the path.

Example: Searching for files related to “Documents” in the home directory

locate ~/Documents

4.2 Filtering Search Results

You can further narrow down search results by using grep in combination with locate.

Example: Displaying only files with the “.txt” extension from the search results

locate example | grep ".txt"

5. Combining the grep Command

When you need to search not just for files but also for content inside files, the grep command is extremely useful.
This section explains how to use grep alone and in combination with find and locate for advanced searches.

5.1 Basics of the grep Command

The grep command searches for lines containing a specified string within a file.

Basic Syntax of the grep Command

grep [options] "search string" [file]

Example: Searching for lines containing “Ubuntu” in the file example.txt

grep "Ubuntu" example.txt

Common grep Options

• -i: Case-insensitive search.
• -r: Recursively search within directories.
• -n: Display line numbers for matched results.

5.2 Using grep with find

You can use find to locate specific files and then search their contents with grep.

Example: Searching for the string “error” inside all .log files

find ~/ -name "*.log" -exec grep "error" {} ;

5.3 Using grep with locate

The locate command can be combined with grep to further refine search results.

Example: Searching for .txt files containing “example” in their name

locate "*.txt" | grep "example"

6. Searching for Files Using GUI Tools

For beginners who are not comfortable with the command-line interface (CLI) or users who prefer intuitive operations, using GUI-based file search tools is a convenient alternative.
This section explains Ubuntu’s built-in search functions and third-party tools.

6.1 Ubuntu’s Built-in File Search

Ubuntu’s file manager (Nautilus) has a built-in file search feature.

How to Search

1. Open the file manager.
2. Select the folder you want to search in.
3. Enter the keyword in the search bar at the top right.

This method is simple and useful for quickly finding images, documents, and other files.

6.2 Third-Party Search Tools

There are several more powerful search tools available for Ubuntu. Here are some examples:

Catfish

A lightweight GUI-based search tool known for its fast search speed.

• Installation Command

sudo apt install catfish

• How to Use
  Simply launch Catfish and enter a keyword in the search bar to display results.

FSearch

A desktop search tool similar to Windows’ “Everything.”

• Installation Command

sudo apt install fsearch

• Features
• Fast search using an indexed database.
• Simple and user-friendly interface.

7. Tips to Improve Search Speed and Efficiency

Optimizing file search speed requires some techniques.
This section introduces specific methods to enhance search efficiency.

7.1 Utilizing Indexing

Using index-based search tools like locate allows for fast searches across a large number of files.
Regularly updating the database ensures that the latest file information is included.

Example: Updating the database

sudo updatedb

7.2 Limiting the Search Scope

Restricting the search range can significantly reduce search time.

• Limit the search to specific directories.
• Exclude unnecessary file types.

Example: Excluding PDF files from the search in the home directory

find ~/ -type f ! -name "*.pdf"

7.3 Using Search Optimization Options

Many commands offer options to improve search speed. For example, the -maxdepth option in find limits the depth of directory searches.

Example: Searching only in the current directory and one level below

find ./ -maxdepth 1 -name "*.txt"

8. Troubleshooting File Search Issues

If file search does not work as expected, here are some common issues and their solutions.

8.1 No Search Results

• Possible Cause 1: The file name is incorrect.
• Solution: Use the case-insensitive -iname option.
• Possible Cause 2: The file is hidden.
• Solution: Add the -name ".*" option to search for hidden files.

8.2 Permission Issues

Some directories require administrative privileges to access.

• Solution: Use sudo to execute the search with elevated privileges.

sudo find / -name "example.txt"

8.3 locate Does Not Show the Latest Files

The locate database may be outdated.

• Solution: Update the database with updatedb.

sudo updatedb

9. Conclusion

File search in Ubuntu can greatly improve workflow efficiency.
By combining the find, locate, and grep commands with GUI tools, you can efficiently locate files with ease.
Try out these methods and enhance your productivity!

That’s all for this article! In the next post, we will cover advanced Linux operations and useful file management tips for Ubuntu. Stay tuned!