Man page says
Files created by zip can be uncompressed by gzip only if they have a
single member compressed with the 'deflation' method. This feature is
only intended to help conversion of tar.zip files to the tar.gz format.
To extract a zip file with a single member, use a command like gunzip
<foo.zip or gunzip -S .zip foo.zip. To extract zip files with several
members, use unzip instead of gunzip.
$ touch /tmp/e.zip
$ gunzip /tmp/e.zip
gzip: /tmp/e.zip: unknown suffix -- ignored
$ touch /tmp/e.tar.zip
$ gunzip /tmp/e.tar.zip
gzip: /tmp/e.tar.zip: unknown suffix -- ignored
$ touch /tmp/x.gz
$ gunzip /tmp/x.gz
gzip: /tmp/x.gz: unexpected end of file #Good. At least suffix is recognized
$ gunzip --version
gunzip (gzip) 1.10
So we see *.zip can't be dealt with at all.
So the man page should say that instead.
Yes maybe other parts of the documentation say something else, but I'm
just talking about the man page.
