On Mon, Jan 24, 2000 at 08:24:37PM +0000, Erich T. Enke wrote:
> I also found these results (using 1.4.1 -- I don't have access to a current
> machine, but may be useful nonetheless):
> 
> sh:   ! ( echo hello | grep h ); echo $?
> sh:   hello
> sh:   1
> bash: ! ( echo hello | grep h ); echo $?
> bash: hello
> bash: 0
> ksh:  ! ( echo hello | grep h ); echo $?
> ksh:  hello
> ksh:  1

As Bruce Momjian pointed out to me, putting () in is subtly different, as it
spawns a subshell to do the pipe, whereas the bit I was complaining about
as per PR bin/9184 is that in the sh(1) manpage:

     The format for a pipeline is:

           [!] command1 [| command2 ...]

     If the reserved word ! does not precede the pipeline, the exit status is
     the exit status of the last command specified in the pipeline.  Other-
     wise, the exit status is the logical NOT of the exit status of the last
     command.

It isn't clear to me what ! should do with the exit status of a subshell -
it seems sh takes the logical not of it correctly from your example.

Cheers,

Patrick

> >sh seems to be broken:
> >
> >quartz% ksh
> >$ echo "$PGDATA" | grep '^/'
> >/usr/local/pgsql/data
> >$ echo $?
> >0
> >$ ! echo "$PGDATA" | grep '^/'
> >/usr/local/pgsql/data
> >$ echo $?
> >1
> >$ quartz% sh
> >$ echo "$PGDATA" | grep '^/'
> >/usr/local/pgsql/data
> >$ echo $?
> >0
> >$ ! echo "$PGDATA" | grep '^/'
> >/usr/local/pgsql/data
> >$ echo $?
> >0
> >
> >That last 0 should be a 1 as per ksh shouldn't it?
> >
> >This is NetBSD/i386-current of 4 Jan (or yesterday not sure).