UNIX for Dummies Questions & Answers

wow, thanks. that's getting there, but the -z won't allow for empty fields, which i think are legal, like this line:

ups::respawn:rtprio 0 /usr/lbin/ups_mond -f /etc/ups_conf

doesn't a blank in the runlevel field indicate this should run at all run levels?

Yeah, that line is legal and my code will not reject it. It this case nf will be 3 because there are 3 non-empty fields. Only records where nf is 0 are discarded, these are blank lines.


If you leave this field empty, it is the same as specifying "0123456", which means that it will not run in run level s.

I see that it works. But somehow I have to count the empty fields, to make sure that there are 4 fields, empty or not. I tried adding an "or" to the test statement (for fields 2 and 4, which can be blank), like this:

[[ ! -z $rstate -o -z $rstate ]] && ((nf=nf+1))

but it complains about the -o option.

This is the test I put for length of id field,
thanks again.

idlength=${#id}

if [ $idlength -ne 0 -a $idlength -le 4 ]; then
:
else
echo "id field must be from 1 to 4 characters"
fi

I also need some way to put the line number of a failing line into an echo statement...

Don't do that. The nf stuff is to detect completely blank lines. If you really wanted to unconditionally increment nf at this point, there is no need to add a test that cannot fail. ((nf=nf+1)) could be used all by itself. Add with ksh [[ or it handled by | not -o.

If you don't care whether or not the field rstate has something, just don't test it. Instead, test the stuff you do care about. You are already checking the id field for the number of characters. That leaves the action field. You can just add a "if [[ -z $action ]]" or maybe you'd rather get the length of the action field and see if it's non-zero.