How to search file content?

To search for specific content within files in Linux, you can use the grep command. Here’s how to use it effectively:

To search for a specific string in a file, use:

grep "search_string" filename.txt

This command will display all lines in filename.txt that contain the specified search_string.

To perform a case-insensitive search, use the -i option:

grep -i "search_string" filename.txt

You can search in multiple files by specifying them:

grep "search_string" file1.txt file2.txt

To search for a string in all files within a directory and its subdirectories, use the -r option:

grep -r "search_string" /path/to/directory

To display the line numbers of matching lines, use the -n option:

grep -n "search_string" filename.txt

To search for whole words only, use the -w option:

grep -w "search_string" filename.txt

Use grep "search_string" filename.txt for basic searches.
Use -i for case-insensitive, -r for recursive, -n for line numbers, and -w for whole word searches.
Combine options as needed, e.g., grep -in "search_string" filename.txt.