I have a file where it contains a list of search patterns (searchPattern.txt). Its contents is similar to the contents below where there are 3000+ of them.123456234567345678...What I wanted to do is to use grep and search directories using the patterns listed in the file if they exist. It would be similar to this kind of command but instead of one search string there are many and its listed in a file.grep searchPattern.txt diagnostics*Although the command above doesn't work its just an idea as to what I wanted to happen.Can this be done with grep? If it can't be done can someone suggest a better way to do this? 
Grep to search directories for patterns inside a text file
linux;command line;grep
Try this one:grep -r -f /path/to/pattern/file diagnostics*