I have a fixed-width-field file which I'm trying to sort using the UNIX (Cygwin, in my case) sort utility.
The problem is there is a two-line header at the top of the file which is being sorted to the bottom of the file (as each header line begins with a colon).
Is there a way to tell sort either "pass the first two lines across unsorted" or to specify an ordering which sorts the colon lines to the top - the remaining lines are always start with a 6-digit numeric (which is actually the key I'm sorting on) if that helps.
Example:
:0:12345
:1:6:2:3:8:4:2
010005TSTDOG_FOOD01
500123TSTMY_RADAR00
222334NOTALINEOUT01
477821USASHUTTLES21
325611LVEANOTHERS00
should sort to:
:0:12345
:1:6:2:3:8:4:2
010005TSTDOG_FOOD01
222334NOTALINEOUT01
325611LVEANOTHERS00
477821USASHUTTLES21
500123TSTMY_RADAR00
(head -n 2 <file> && tail -n +3 <file> | sort) > newfile
The parentheses create a subshell, wrapping up the stdout so you can pipe it or redirect it as if it had come from a single command.