egrep - Search a file for a specified pattern

Format

egrep [-BNbcilnqsvx] [-A|-P|-C num] [-S string]
[-W option[option] ... [-e pattern] file ... [-f patternfile] file ... [pattern] [file ...]

The egrep utility is fully supported for compatibility with older UNIX systems. However, use grep -E instead because it might provide greater functionality and is considered the standard for portable UNIX applications as defined by POSIX.2 IEEE standard 1003.2-1992.