For this, we can use a pipe operator and the echo command with grep. Here, the output from the echo command is read by the grep command. Consequently, grep prints each string or text containing the character s. If the terminal supports color, we can see the character highlighted in red.

The grep command is a useful tool for finding all occurrences of a search term in a selection of files or the output of another command. It can also come in handy when filtering a log file or stream and when used as part of a script or chain of commands.

Search string in current folder: grep -iR "5464" . The command grep -iR "5464" . searches for the string "5464" in all files under the current directory (represented by . ), recursively, and displays the matching lines along with the filenames where the string appears, ignoring the case of the characters.

If the pattern is found, grep returns an exit status of 0, indicating success; if grep cannot find the pattern, it returns 1 as its exit status; and if the file cannot be found, grep returns an exit status of 2.