find by name, type, and size in Linux CLI - Commands & Configuration

Introduction

Sometimes you need to locate files on your computer based on their name, type, or size. The Linux find command helps you search for files that match these conditions quickly and easily.

When you want to find all text files named report.txt in your documents folder.

When you need to locate all directories named backup on your system.

When you want to find files larger than 10 megabytes to free up disk space.

When you want to list all executable files in a specific folder.

When you want to combine conditions, like finding all log files larger than 5MB.

Commands

This command searches in /home/user/documents for files named exactly report.txt.

Terminal

find /home/user/documents -name "report.txt"

Expected Output

/home/user/documents/project/report.txt

/home/user/documents/old_reports/report.txt

→

-name - Search files by exact name pattern.

This command finds directories (-type d) named backup anywhere under /home/user.

Terminal

find /home/user -type d -name "backup"

Expected Output

/home/user/documents/backup

/home/user/backup

→

-type d - Limit search to directories only.

→

-name - Match directory name.

This command finds files (-type f) larger than 10 megabytes (+10M) in /var/log.

Terminal

find /var/log -type f -size +10M

Expected Output

/var/log/large_log1.log

/var/log/large_log2.log

→

-type f - Limit search to files only.

→

-size +10M - Find files larger than 10 megabytes.

This command lists all executable files in /usr/local/bin.

Terminal

find /usr/local/bin -type f -executable

Expected Output

/usr/local/bin/script1

/usr/local/bin/tool

→

-type f - Limit search to files.

→

-executable - Find files with execute permission.

This command finds all log files larger than 5 megabytes in /home/user/logs.

Terminal

find /home/user/logs -type f -name "*.log" -size +5M

Expected Output

/home/user/logs/error.log

/home/user/logs/access.log

→

-type f - Search files only.

→

-name - Match files ending with .log.

→

-size +5M - Files larger than 5 megabytes.

Key Concept

If you remember nothing else from this pattern, remember: the find command lets you combine name, type, and size filters to pinpoint exactly the files or directories you need.

Common Mistakes

Using -name without quotes around the pattern

The shell may expand wildcards before find runs, causing unexpected results.

Always put the pattern in quotes, like -name "*.txt".

Using -size 10M instead of +10M or -10M

-size 10M finds files exactly 10 megabytes, which is rare and often not what you want.

Use +10M to find files larger than 10MB or -10M for smaller than 10MB.

Not specifying -type when searching by name

You might get both files and directories matching the name, which can be confusing.

Add -type f for files or -type d for directories to narrow results.

Summary

Use find with -name to search files or directories by their name.

Add -type f or -type d to limit results to files or directories.

Use -size with + or - and a size unit (c, k, M, G) to filter by file size.

Practice

1. What does the find command option -name do in Linux CLI?

easy

A. Searches files or directories by their name pattern

B. Filters files by their size

C. Lists all files in the current directory

D. Changes the name of a file

Solution

1. Step 1: Understand the -name option

   The -name option in the find command is used to search for files or directories that match a specific name pattern.

2. Step 2: Compare with other options

   Options like filtering by size or listing files are done with other flags, not -name.

3. Final Answer:

   Searches files or directories by their name pattern -> Option A

4. Quick Check:

   -name = Search by name [OK]

Hint: Remember: -name matches file names exactly [OK]

Common Mistakes:

• Confusing -name with size filters
• Thinking -name lists files
• Using -name to rename files

2. Which of the following is the correct syntax to find all regular files named report.txt in the current directory and its subdirectories?

easy

A. find . -type f -name report.txt

B. find . -name "report.txt" -type d

C. find . -type f -name "report.txt"

D. find / -type f -name report.txt

Solution

1. Step 1: Understand the syntax for find

   The correct syntax requires the path (here . for current directory), the type -type f for regular files, and the name pattern with quotes -name "report.txt" to match the exact file name.

2. Step 2: Check each option

   find . -type f -name report.txt misses quotes around the name, which can cause issues with special characters. find . -name "report.txt" -type d searches for directories (-type d) not files. find / -type f -name report.txt searches from root /, not current directory. find . -type f -name "report.txt" is correct with quotes and correct type.

3. Final Answer:

   find . -type f -name "report.txt" -> Option C

4. Quick Check:

   Quotes + correct type + current dir = find . -type f -name "report.txt" [OK]

Hint: Always quote the name pattern to avoid shell issues [OK]

Common Mistakes:

• Omitting quotes around the name
• Using wrong type flag (-type d instead of -type f)
• Searching from wrong directory

3. What will be the output of the command find /tmp -type f -size +1M -name "*.log" assuming there are two files: /tmp/app.log (500K) and /tmp/error.log (2M)?

medium

A. /tmp/app.log
/tmp/error.log

B. /tmp/error.log

C. /tmp/app.log

D. " (no output)

Solution

1. Step 1: Understand the command filters

   The command searches in /tmp for regular files (-type f) with size greater than 1 megabyte (-size +1M) and names ending with .log (-name "*.log").

2. Step 2: Apply filters to given files

   /tmp/app.log is 500K, which is less than 1M, so excluded. /tmp/error.log is 2M, which matches size and name filters, so included.

3. Final Answer:

   /tmp/error.log -> Option B

4. Quick Check:

   Size +1M and name *.log = /tmp/error.log [OK]

Hint: Size +1M means files larger than 1 megabyte [OK]

Common Mistakes:

• Including files smaller than 1M
• Ignoring the name pattern
• Confusing +1M with exactly 1M

4. You run the command find . -type f -name *.txt -size -10k but get an error or unexpected results. What is the likely problem?

medium

A. The command needs sudo to run

B. Wrong size flag; should be +10k instead of -10k

C. Using -type f instead of -type d

D. Missing quotes around *.txt causing shell expansion

Solution

1. Step 1: Identify the issue with -name pattern

   The pattern *.txt without quotes is expanded by the shell before find runs, causing unexpected behavior or errors.

2. Step 2: Correct usage with quotes

   Enclosing *.txt in quotes like "*.txt" prevents shell expansion and lets find correctly match file names.

3. Final Answer:

   Missing quotes around *.txt causing shell expansion -> Option D

4. Quick Check:

   Always quote patterns in -name [OK]

Hint: Quote wildcards in -name to avoid shell expansion [OK]

Common Mistakes:

• Not quoting the name pattern
• Confusing size flags + and -
• Using wrong type flag

5. You want to find all directories named backup larger than 100MB inside /var. Which command correctly achieves this?

hard

A. find /var -type d -name "backup" -size +100M -exec du -sh {} \;

B. find /var -type d -name "backup" -size +100M

C. find /var -type d -name "backup" -exec du -sh {} \; | awk '$1 > 100M'

D. find /var -type d -name "backup" -size +100M -size +100M

Solution

1. Step 1: Understand find limitations on directory size

   The -size option measures file size, but for directories it measures disk usage metadata, not total content size.

2. Step 2: Use -exec du -sh to get actual directory size

   find /var -type d -name "backup" -size +100M -exec du -sh {} \; uses -exec du -sh {} to show human-readable size of each directory found, which helps verify size over 100MB.

3. Step 3: Confirm correct filtering

   find /var -type d -name "backup" -size +100M incorrectly uses -size +100M on directories which is unreliable. find /var -type d -name "backup" -exec du -sh {} \; | awk '$1 > 100M' tries to filter with awk but size format is not numeric only. find /var -type d -name "backup" -size +100M -size +100M repeats -size +100M unnecessarily.

4. Final Answer:

   find /var -type d -name "backup" -size +100M -exec du -sh {} \; -> Option A

5. Quick Check:

   Use -exec du -sh to check directory sizes [OK]

Hint: Use du with -exec to measure directory size [OK]

Common Mistakes:

• Relying on -size for directory content size
• Not quoting the name pattern
• Repeating size filters unnecessarily