Hi Jim,

The continuous integration at https://gitlab.com/gnu-gzip/ci-distcheck/
shows a test failure:

FAIL: write-error
=================
../../../sources/gzip/build-aux/test-driver: line 107: ../../../sources/gzip/tests/write-error: Permission denied
FAIL write-error (exit status: 126)

A simple 'chmod a+x tests/write-error' fixes this one, for non-root
users.

When I run "make check" as root — which happens to be what the CI does —
I get another test failure:

FAIL write-error (exit status: 1)

The reason here is that even after 'chmod a-w d', the directory 'd'
is writable.

This patch fixes both issues. "make check" now passes again, both as a
normal user and as root.