egrep

Find patterns in files using extended regular expression (supports ?, +, {}, () and |). More information: https://manned.org/egrep.

• Search for a pattern within a file:

egrep "search_pattern" path/to/file

• Search for a pattern within multiple files:

egrep "search_pattern" path/to/file1 path/to/file2 ...

• Search stdin for a pattern:

cat path/to/file | egrep search_pattern

• Print file name and line number for each match:

egrep --with-filename --line-number "search_pattern" path/to/file

• Search for a pattern in all files recursively in a directory, ignoring binary files:

egrep --recursive --binary-files=without-match "search_pattern" path/to/directory

• Search for lines that do not match a pattern:

egrep --invert-match "search_pattern" path/to/file