How can I use diff to difference between programs output?

nadavvin · 08-05-2006, 03:30 AM

Hello

How can I use diff to difference between programs output?
I can use diff with files: diff a b
How can I use in programs output?

I try diff `a.sh` b
but I get error of too many parameters.

acid_kewpie · 08-05-2006, 03:32 AM

you need to redirect the output to a file for at least one. i assume you could pipe the input in for one...

./scriptname | diff filename

nadavvin · 08-05-2006, 04:17 AM

thanks.

but it is ./scriptname | diff - filename

spirit receiver · 08-05-2006, 04:31 AM

You can also use process redirection:

Code:

#! /bin/bash
exec 3< <(ls ~)
exec 4< <(echo "Hi"; ls ~)
diff /dev/fd/3 /dev/fd/4

theYinYeti · 08-05-2006, 04:35 AM

Or more simply, on the command line:

Code:

diff <(command 1) <(command 2)

bash is wonderful, isn't it

Yves.