Categories
bash mysql

Bash / MySQL queries…

Reduce connection counts to MySQL by using an array to get many values at once (assuming they’re single ‘word’ values)

Categories
bash sysadmin

Avoiding unnecessary commands in bash….

Some alternative bash things…. ( avoiding unneecessary use of cat / awk / grep …. )

Categories
linux

Bash random number generation

Historically I’ve used $RANDOM as a random number source in bash — a bit like : RAND=$(( $RANDOM % 10 )) when I’ve needed a random number out of 0,1,2,3,4,5,6,7,8 and 9 one problem with this is that $RANDOM itself is populated between 0 and 32767 by the shell – so it’s not going to […]

Categories
linux

Sponge – Shell command

Today, my sed kung-foo seemed to be lacking, so I ended up having to split the sed command over a zillion lines… Normally I’d do something like : sed ‘s/foo/bar/g’ tmp.txt > tmp2.txt sed ‘s/fo2/blah/g’ tmp2.txt > tmp3.txt But this obviously gets painful after a time, a different approach would be to use sponge where […]