tldr/pages/common/grep.md

grep

Find patterns in files using regular expressions. More information: https://www.gnu.org/software/grep/manual/grep.html.

• Search for a pattern within a file:

grep "{{search_pattern}}" {{path/to/file}}

• Search for an exact string (disables regular expressions):

grep {{-F|--fixed-strings}} "{{exact_string}}" {{path/to/file}}

• Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:

grep {{-r|--recursive}} {{-n|--line-number}} --binary-files {{without-match}} "{{search_pattern}}" {{path/to/directory}}

• Use extended regular expressions (supports ?, +, {}, () and |), in case-insensitive mode:

grep {{-E|--extended-regexp}} {{-i|--ignore-case}} "{{search_pattern}}" {{path/to/file}}

• Print 3 lines of context around, before, or after each match:

grep --{{context|before-context|after-context}} {{3}} "{{search_pattern}}" {{path/to/file}}

• Print file name and line number for each match with color output:

grep {{-H|--with-filename}} {{-n|--line-number}} --color=always "{{search_pattern}}" {{path/to/file}}

• Search for lines matching a pattern, printing only the matched text:

grep {{-o|--only-matching}} "{{search_pattern}}" {{path/to/file}}

• Search stdin for lines that do not match a pattern:

cat {{path/to/file}} | grep {{-v|--invert-match}} "{{search_pattern}}"