The Guile process taking the role of PID 1 during Guix builds does not reap
zombie processes, which makes them continue responding to "kill -0".

--- a/src/testsuite/stop-server.sh	2015-02-05 11:24:00.535908842 +0100
+++ b/src/testsuite/stop-server.sh	2015-02-05 11:25:00.264351349 +0100
@@ -1,6 +1,21 @@
 #!/bin/sh
 # ngIRCd Test Suite
 
+process_is_alive(){
+    ! process_is_dead "$1" && ! process_is_undead "$1"
+}
+
+process_is_dead(){
+    ! kill -0 "$1"
+}
+
+process_is_undead(){
+    case $(ps -p "$1" -o state=) in
+        (Z*) true ;;
+        (*) false ;;
+    esac
+}
+
 [ -z "$srcdir" ] && srcdir=`dirname $0`
 
 # read in functions
@@ -24,7 +40,7 @@
 
 # waiting ...
 for i in 1 2 3 4 5; do
-  kill -0 $pid > /dev/null 2>&1; r=$?
+  process_is_alive $pid > /dev/null 2>&1; r=$?
   if [ $r -ne 0 ]; then
     echo " ok".
     exit 0
ts</option>
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<div class='path'>path: <a href='/guix/log/?id=b73b056abbed1b031360b8cbb1a8e23aa07bca60'>root</a>/<a href='/guix/log/tests?id=b73b056abbed1b031360b8cbb1a8e23aa07bca60'>tests</a>/<a href='/guix/log/tests/guix-pack-relocatable.sh?id=b73b056abbed1b031360b8cbb1a8e23aa07bca60'>guix-pack-relocatable.sh</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/guix-pack-relocatable.sh?id=b73b056abbed1b031360b8cbb1a8e23aa07bca60&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-04-21 16:16:38 +0200'>2023-04-21</span></td><td><a href='/guix/commit/tests/guix-pack-relocatable.sh?id=37dd69b44511dc73eb04bdebe8d82c9a0386338e'>tests: Fix checks for expected failures.</a><span class='msg-avail'>...<span class='msg-tooltip'>Addresses &lt;https://issues.guix.gnu.org/62406&gt;.

With 'set -e', a return status inverted with '!' does not cause the shell to
exit immediately.  Instead use '&amp;&amp; false' to indicate an expected failure.

* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh,
tests/guix-environment-container.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-home.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh, tests/guix-refresh.sh, tests/guix-shell.sh,
tests/guix-style.sh, tests/guix-system.sh: Replace uses of '! ...' with
'... &amp;&amp; false' or `test ! ...` as appropriate.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2023-02-27 23:40:43 +0100'>2023-02-27</span></td><td><a href='/guix/commit/tests/guix-pack-relocatable.sh?id=92a0e60a963a54230e400c5c2ae585205489bf35'>pack: Adjust shell tests to read-only tarball root.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://issues.guix.gnu.org/61853&gt;.

Fixes a regression introduced in
68380db4c40a2ee1156349a87254fd7b1f1a52d5, whereby the tarball's root
entry is now read-only, due to the creation of "profile-directory" in
the store.

* tests/guix-pack.sh: Remove and recreate $test_directory before
transformation option test.
* tests/guix-pack-relocatable.sh: Add "chmod +w $test_directory" lines
before attempts to write to it.
</span></span></td><td>Ludovic Courtès</td></tr>