[SOLVED] Bash script to remove some keywords in a txt file

Issue

i am not familiar with bash script, after some research, i found some hints but still need your effort.

Given i have a resources.txt, contains

a
b
c
d

and a whitelist.txt file, contains

c
d

I would like to remove all items that exactly match from whitelist file to resource file. so the expected output is

a
b

Expect c and d is removed because they are in whitelist file.

I have created below script to read it, but don't know how to replace each one by one to resource file.

# read the whitelist file
echo whitelist.txt | awk '{for (i=1; i<=NF; i++) printf "%s\n",$i}

# replace item in resource file
awk '{sub(/c/,""); print}' resources.txt

Your help is greatly appreciated, thanks a lot!!

Solution

I would use this grep:

grep -Fvxf whitelist.txt resources.txt

• -F fixed/literal strings (no regex)
• -f FILE get patterns from FILE
• -x match the whole line
• -v print lines which don't match
• This grep is POSIX

Answered By - dan

Answer Checked By - Mildred Charles (WPSolving Admin)