How to Find Files Using Wildcards in Linux

When managing files across multiple directories, you often need to locate files based on name patterns rather than exact names. Linux provides robust wildcard matching capabilities through the find command, allowing you to search recursively through directory structures using flexible pattern matching.

Prerequisites

You'll need access to a Linux terminal. The examples work on all major Linux distributions and macOS.

Basic Wildcard Patterns

The find command uses several wildcard characters for pattern matching. The asterisk (*) matches any number of characters, while the question mark (?) matches exactly one character.

This command finds all Python files in the current directory and its subdirectories:

find . -name "*.py"

The dot represents the current directory, and the pattern *.py matches any filename ending with .py. The quotes prevent the shell from expanding the wildcard before passing it to find.

Finding Files with Multiple Extensions

You can search for files with different extensions using the -o (OR) operator. This command locates both JavaScript and TypeScript files:

find . \( -name "*.js" -o -name "*.ts" \)

The parentheses group the conditions, ensuring the OR logic applies correctly. This approach is useful when working with projects that use multiple related file types.

Case-Insensitive Wildcard Matching

Sometimes you're unsure about the case of file extensions or names. The -iname option performs case-insensitive matching:

find /home/user/documents -iname "*.PDF"

This command finds PDF files regardless of whether the extension is .pdf, .PDF, or .Pdf, which is helpful when dealing with files from different operating systems.

Using Question Mark for Single Character Matching

The question mark wildcard matches exactly one character. This command finds files like log1.txt, log2.txt, but not log10.txt:

find /var/log -name "log?.txt"

This pattern is particularly useful when searching for numbered files with predictable naming conventions.

Finding Files Starting with Specific Patterns

You can search for files that begin with certain text. This command finds all configuration files that start with "nginx":

find /etc -name "nginx*"

This matches files like nginx.conf, nginx.conf.backup, or nginx-site-available, making it easy to locate related configuration files.

Combining Wildcards with Directory Paths

Wildcards work within directory paths as well. This command searches for CSS files within any assets directory:

find . -path "*/assets/*.css"

The -path option matches against the entire file path, not just the filename. This approach helps you locate files in specific directory structures within larger projects.

Finding Files with Specific Character Sets

You can use bracket notation to match specific character sets. This command finds log files for specific months:

find /var/log -name "access-2024-[01][0-9]-*.log"

This pattern matches log files from January through December 2024, with any day and additional text after the date. The bracket notation [01] matches either 0 or 1, while [0-9] matches any digit.

Excluding Certain Patterns

Sometimes you need to find files that don't match a pattern. This command finds all files except those ending in .tmp:

find . -type f ! -name "*.tmp"

The exclamation mark negates the condition, and -type f ensures you only match regular files, not directories.

Finding Files by Size and Pattern

You can combine wildcard patterns with other find criteria. This command locates large image files:

find . -name "*.jpg" -size +1M

This finds JPEG files larger than 1 megabyte, which is useful for identifying files that might need compression or optimization.

Using Find with Maximum Depth

When you want to limit how deep the search goes into subdirectories, use the -maxdepth option:

find . -maxdepth 2 -name "*.json"

This command only searches the current directory and one level of subdirectories for JSON files, preventing unnecessarily deep searches in large directory structures.

Advanced Pattern Matching with Regular Expressions

For more complex patterns, you can use regular expressions with the -regex option:

find . -regex ".*\.\(jpg\|png\|gif\)$"

This finds files ending with any of the three image extensions. Regular expressions provide more flexibility than basic wildcards for complex matching requirements.

Performance Considerations

When searching large directory trees, consider using the -type f option to only match files:

find /home -type f -name "*.log"

This prevents the command from trying to match directories against your pattern, improving performance and reducing irrelevant matches.

Next Steps

You can now efficiently locate files using pattern matching across your filesystem. Consider combining these techniques with other find options like -mtime for date-based searches or -exec to perform actions on found files. You might also explore locate and updatedb for faster searching of frequently accessed files.

Good luck with your file searches!