docs/Makefile.sh: Fix the attempt to determine what directory

vagrantc · vagrantc · commit abc35263de31 · 2026-04-28T12:40:33.000-07:00
Makefile.sh is in.

Checking ${1} resulted in a empty/null value, which was worked around
in debian/rules by manually changing to the correct directory, but
this only hid the bug. The correct variable to check is ${0}.

When run with bash as /bin/sh, changes in behavior with bash 5.3 in
handling "cd" with an empty argument revealed the bug by not creating
any manpages, and bash emitting an error.

This was discovered when ltsp started failing to build reproducibly on
tests.reproducible-builds.org, where /bin/sh points to bash in one
test.

Big thanks to Chris Lamb who identified the issue and the proper
fix!
diff --git a/docs/Makefile.sh b/docs/Makefile.sh
@@ -205,7 +205,7 @@ main() {
     fi
     echo "Using $cmd to generate the man pages"
 
-    cd "${1%/*}"
+    cd "${0%/*}"
     if is_command dpkg-parsechangelog; then
         _VERSION=$(dpkg-parsechangelog -l ../debian/changelog -S VERSION)
     else
