Awk magic to replace: cat /etc/sybase/interfaces | grep -A 1 -e "$SEARCH" | grep query | awk '{ print $4 }' | awk -F'.' '{print $2}'
If you don't have nl on your system, this achieves a similar effect, the default behavior in nl is to not number blank lines, but this does.
I needed to add a line to my crontab from within a script and didn't want to have to write my own temporary file.
You may find you need to reload the crond after this to make the change take effect.
e.g.:
if [ -x /sbin/service ]
then
/sbin/service crond reload
else
CRON_PID=`ps -furoot | awk '/[^a-z]cron(d)?$/{print $2}'`
if [ -n "$CRON_PID" ]
then
kill -HUP $CRON_PID
fi
fi
The reason I had CRON_HOUR and CRON_MINS instead of numbers is that I wanted to generate a random time between midnight & 6AM to run the job, which I did with:
CRON_HOUR=`/usr/bin/perl -e 'printf "%02d\n", int(rand(6))'`
CRON_MINS=`/usr/bin/perl -e 'printf "%02d\n", int(rand(60));'`
print the lines of a file in randomized order Show Sample Output
Once I wrote a command line calculator program in C, then I found this... and added to it a bit.
For ease of use I normally use this in a tiny Perl program (which I call pc for 'Perl Calculator')
#!/usr/bin/perl -w
die "Usage: $0 MATHS\n" unless(@ARGV);for(@ARGV){s/x/*/g;s/v/sqrt /g;s/\^/**/g};
print eval(join('',@ARGV)),$/;
It handles square roots, power, modulus:
pc 1+2 (1 plus 2)
3
pc 3x4 (3 times 4)
12
pc 5^6 (5 to the power of 6)
15625
pc v 49 ( square root of 49 )
7
pc 12/3 (12 divided by 3)
4
pc 19%4 (19 modulus 4)
3
(you can string maths together too)
pc 10 x 10 x 10
1000
pc 10 + 10 + 10 / 2
25
pc 7 x v49
49
Show Sample Output
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