Ubuntu – How to grep same strings by comparing two files

Try this command:

 grep -v -f file2.csv file1.csv > file3.csv

According to grep manual:

  -f FILE, --file=FILE
          Obtain  patterns  from  FILE,  one  per  line.   The  empty file
          contains zero patterns, and therefore matches nothing.   (-f  is
          specified by POSIX.)

  -v, --invert-match
          Invert the sense of matching, to select non-matching lines.  (-v
          is specified by POSIX.)

As Steeldriver said in his comment is better add also -x and -F that:

  -F, --fixed-strings
          Interpret PATTERN as a  list  of  fixed  strings,  separated  by
          newlines,  any  of  which is to be matched.  (-F is specified by
          POSIX.)
  -x, --line-regexp
          Select  only  those  matches  that exactly match the whole line.
          (-x is specified by POSIX.)

So, better command is:

 grep -xvFf file2.csv file1.csv > file3.csv

This command use file2.csv line as pattern and print line of file1.csv that doesn't match (-v).

Just in case the files are very large and making two passes on them is expensive and you want just the filenames, using find+awk:

find . -type f -exec awk 'FNR == 1 {a=0; r=0} /AccessToken/{a=1} /Registrationrequest/{r=1} a && r {print FILENAME; nextfile}' {} +

• we set two flag variables a and r for when the corresponding patterns were found, cleared at the start of each file (FNR == 1)
• when both variables are true, we print the filename and move on to the next file.