Re: [Quilt-dev] [patch 3/8] tac is not portable

[Jean Delvare]

Hi Gary,

> No, I mean that with that syntax you are running:
> 
>   (time head -n 500 <largefile;) | gtac
> 
> not:
> 
>   time (head -n 500 < large file | gtac)

I don't think so, not on my system at least.

$ time true | sleep 1

real    0m1.012s
user    0m0.004s
sys     0m0.004s

$ (time true) | sleep 1

real    0m0.007s
user    0m0.004s
sys     0m0.004s

I guess the left-hand side of the pipe needs to wait for the right-hand
side of the pipe to exit before it can exit itself, in order to get the
return code or something alike.

Oddly enough, 

$ time (true | sleep 1)

returns only after the 1 second sleep, but doesn't print anything. I
have no idea why.

-- 
Jean Delvare