Using fgrep with 'if' in shell scripts

[Fozzeebear]

I am trying (and unfortunately failing!) to write a short Unix script to do the following:

1) do a fgrep search for required strings within a file
2) if there are matches, do nothing
3) if there are no matches, print an error message

The sort of thing I have been trying is:

if test 'fgrep -f list filename' = 0 ;
then echo "error";
fi

But, this does not work. Any help (or suggestions for a simpler approach) will be much appreciated...

 

[stanhubble]

It is suggested to use grep -F instead of fgrep

try
if [ `grep -F -f list filename > /dev/null` = 0 ] ; then
echo "error"
fi

or
grep -F -f list filename > /dev/null
if [ $? = 0 ] ; then
echo "error"
fi

 

[PHV]

Try something like this:

fgrep -f list filename >/dev/null || echo "error"

The man page of fgrep should give you the exit codes.

Hope This Help
PH.