bash. Grep text file looking for lines from other file [duplicate] - bash

Question

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Intersection of files
(4 answers)
Closed 3 years ago.
Is it possible to analize text file let's say log.txt looking for lines from the other file - let's say config.txt. I tried to do following thing:
while read -r line;
do
if grep -q $line $log_path; then
echo "Found line: $line" >> $out_log
break
else echo "Line not found: $line" >> $out_log
fi
done < $conf_path
$conf_path is a path like /path/to/config.txt
$log_path is a path like /path/to/log.txt
and the $out_log is the /path/to/output_log.txt which is used to test if script works properly.
Example $line is "ERROR: MESSAGE: \[Library not found \!\]". I tested grep instruction outside the script and it found that line properly, so I do not think that grep is the problem here. Every time else statement is executed.
Thank you, Community, for any suggestions,
Best regards, Max

Answer 1

Try below
Code:
while read -r line
do if grep -q "${line}" $log_path
then echo "Found line: $line" >> $out_log
else echo "Line not found: $line" >> $out_log
fi
done < $conf_path
Example:
bash-3.2$ echo $conf_path ; cat $conf_path
config.txt
ERROR: MESSAGE: \[Library not found \!\]
ERROR: MESSAGE: \[File not found \!\]
ERROR: MESSAGE: \[Path not found \!\]
ERROR: MESSAGE: \[Permission denied \!\]
bash-3.2$
bash-3.2$ echo $log_path; cat $log_path
log.txt
INFO: MESSAGE: Script Starts
INFO: MESSAGE: Some command output
ERROR: MESSAGE: [Library not found !]
INFO: MESSAGE: Some other command output
ERROR: MESSAGE: [Path not found !]
INFO: MESSAGE: Exit script with 2
bash-3.2$
bash-3.2$ while read -r line; do if grep -q "${line}" $log_path; then echo "Found line: $line" >> $out_log; else echo "Line not found: $line" >> $out_log; fi; done < $conf_path
bash-3.2$
bash-3.2$ echo $out_log; cat $out_log
output_log.txt
Found line: ERROR: MESSAGE: \[Library not found \!\]
Line not found: ERROR: MESSAGE: \[File not found \!\]
Found line: ERROR: MESSAGE: \[Path not found \!\]
Line not found: ERROR: MESSAGE: \[Permission denied \!\]
bash-3.2$
Hope this helps. Good Luck !!