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Commands by JohnGH from sorted by
Terminal - Commands by JohnGH - 6 results
cat file | paste -s -d'%' - | sed 's/\(^\|$\)/"/g;s/%/","/g'
awk '/^'$SEARCH'[ ]*$/{getline;if ($1 ~ /query/) {split($4,a,".");print a[2]}}' /etc/sybase/interfaces
2010-12-17 13:24:27
User: JohnGH
Functions: awk
0

Awk magic to replace:

cat /etc/sybase/interfaces | grep -A 1 -e "$SEARCH" | grep query | awk '{ print $4 }' | awk -F'.' '{print $2}'

grep -n "^" <filename>
2010-01-07 14:54:29
User: JohnGH
Functions: grep
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.

crontab -l | sed -e '$G;$s-$-'"$CRON_MINS $CRON_HOUR"' * * * /usr/bin/command >/dev/null 2>&1-' | crontab -
2010-01-07 11:00:05
User: JohnGH
Functions: crontab sed
-1

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));'`
perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt
perl -e 'for(@ARGV){s/x/*/g;s/v/sqrt /g;s/\^/**/g};print eval(join("",@ARGV)),$/;'
2009-12-21 21:03:27
User: JohnGH
Functions: perl
2

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