Re: POSIX conformance in coreutils

[Stephane Chazelas <Stephane_Chazelas@xxxxxxxx>]

On Tue, Jan 11, 2005 at 08:01:26PM -0500, Vin Shelton wrote:
> GNU coreutils (at least versions 5.2.1 and 5.3.0) enforce POSIX
> conformance, so they don't like 'tail -1', instead they require
> 'tail -n 1'.
> 
> This causes problems in E01options.tst:
> 
>   # Count the number of directories on the stack.  Don't care what they are.
>   dircount() { dirs -v | tail -1 | awk '{ print $1 + 1}'; }
> 
> tail: `-1' option is obsolete; use `-n 1'
> Try `tail --help' for more information.
[...]

YMMV.

~$ tail --version
tail (coreutils) 5.2.1
[...]
~$ tail -1 /dev/null
~$

tail -n 1, even if POSIX, is not portable. I think I've come
across a system where it was not supported recently (maybe
Solaris).


>   dircount() { dirs -v | tail -1 | awk '{ print $1 + 1}'; }

Maybe:

dircount() { print $((${${(z)${(f)"$(dirs -v)"}[-1]}[1]} + 1)); }

Or:

dircount() { dirs -v | awk '{n=$1}END{print n+1}'; }

-- 
Stéphane