Your bug report

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

which was filed against the grep package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 30550@debbugs.gnu.org.

-- 
30550: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=30550
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