Grep 3.3 Description:
Grep To use Grep from the command-line, you will have to type the ‘grep --help’ command in a terminal emulator or directly in the Linux console, which will output all the available options, as well various examples on how to use the tool to find a certain pattern into a file. The standard usage example given by the aforementioned command is “grep [OPTION]... PATTERN [FILE]...” The most basic example is “grep -i 'hello world' menu.h main.c”, where “-i” is the [OPTION] “hello world” is the [PATTERN] and “menu.h” and “menu.c” are the [FILE]. This simple command is used for searching for the “hello world” pattern in each of the given files. Keep in mind though, that [PATTERN] is, by default, a Basic Regular Expression (BRE).