Removing lines that are in fileB from fileA producing fileC

Problem

You have two different files fileA and fileB containing similar records (one record per line), and you would like to remove the records that fileB contains from fileA (subtract) producing a new file (fileC) that contains only records that are contained in fileA with records from fileB removed.

Solution

Use the following grep command

grep -vxf fileB fileA > fileC

Search for content in files in linux (recursively and case-independent)

Problem

You would like to find the files that contain some specific text, and would like to do it recursively (ie in a project folder), using something simpler than the find command.

Solution

You can use the following in your current top folder to search recursively, case-independent and by displaying the file number that the searched text appears, with the following:

grep -rin "TextToBeSearched" .