using grep command in unix code example
Example: linux grep
# EXAMPLE 1: look for any files (with names ending in ".c++") for the text "::MethodA("
grep "::MethodA(" *.c++
# EXAMPLE 2: display only the matching file names (not the row too) of the matches
grep -l "MethodA(" *.c++
# SYNTAX
# grep [optional-filters] ""
# OPTIONAL-FILTERS
# +--------+----------------------------------------------------------------------------+
# | OPTION | DESCRIPTION |
# +--------+----------------------------------------------------------------------------+
# | -e | pattern |
# | -i | Ignore uppercase vs. lowercase. |
# | -v | Invert match. |
# | -c | Output count of matching lines only. |
# | -l | Output matching files only. |
# | -n | Precede each matching line with a line number. |
# | -b | A historical curiosity: precede each matching line with a block number. |
# | -h | Output matching lines without preceding them by file names. |
# | -s | Suppress error messages about nonexistent or unreadable files. |
# | -x | |
# | -f | file: Take regexes from a file. |
# | -o | Output the matched parts of a matching line. |
# +--------+----------------------------------------------------------------------------+