How to make “grep” read patterns from a file?

问题:

Suppose there is a large text file and I would like to print only the lines that do not match some patterns. Obviously, I can use egrep -v 'patter1|pattern2|pattern3. Now what if all those patterns are in a text file ? What is the best way to make egrep read patterns from the file ?

回答1:

grep -v -f pattern_file

回答2:

egrep has an -f option which does exactly that: you specify a file, and it reads patterns from that file, one per line.