Re: sed "Hello, world!" program?

Il 21/02/2014 19:47, [email protected] ha scritto:
> 4) It does not rely on "echo" or other non-sed command (that may not be
> present). It makes it's own input, whatever text --version happens to
> produce. Maybe some sed versions may not have --version option? But it
> is a standard command line option, so I think it is fine for this purpose.
>

What if some sed versions have a --version that writes to stderr rather 
than stdout?  In fact it is not a standard option, and an unrecognized 
option would write a message to stderr, not stdout.  So you need a 2>&1.

Paolo