bug#30550: zgrep over multiple files returns 1 if pattern not found in a single file even if found in other files

[Paul Eggert]

On 02/20/2018 07:01 AM, David McCauley wrote:
zgrep version: 1.5

That's pretty old. The bug should be fixed in the current zgrep version 
(1.9). See:

https://bugs.gnu.org/17760