Hi All,
tasty heading..? Ok, whilst I enjoy spinning people with the following, "Nah, mate, don't use Windows", which usually gets the suprised response, "oh, what do u use, MAC". Of which I reply, "ah, u all know what I reply with". BUT, I feel I'm not really a Linux person unless I've mastered, Shell Programming, where I believe the real power of Linux World exists. Anyway, enough dribble, and on to my question of the day. I'm following this tut,
http://www.tldp.org/LDP/abs/html/sha-bang.html
and in the code on that page, there is are variables, $1 and $LINES. Um, what are they..?
if [ -n "$1" ]
# Test if command line argument present (non-empty).
then
lines=$1
else lines=$LINES # Default, if not specified on command line.
fi
and then further down, I see this use of one of them,
tail -$lines messages > mesg.temp # Saves last section of message log file. mv mesg.temp messages # Becomes new log directory.
Can anyone explain this in plain English.? I understand that a portion of messages is being written to mesg.temp, and that the rest is deleted. Just don't get where $1 and $LINES is being generated from. Cheers.
Mark Sargent.
