Hi,
I was playing with set -m and trapping CHLD in a script, and found
the following error:
$ cat setm-bad.bash
set -m
i=0
trap ':; ((++i<5)) && { f & }' CHLD
f(){ echo x; }
f &
wait
$ cat setm.bash
set -m
i=0
trap '((++i<5)) && { f & }' CHLD
f(){ echo x; }
f &
wait
$ cat reproduce.bash
for bash in /bin/bash ~/local/bin/bash ~/bb/prefix/bin/bash; do
echo "$bash"
"$bash" --version |& head -n1
echo setm.bash
"$bash" setm.bash
echo setm-bad.bash
"$bash" setm-bad.bash
echo =====
done
$ bash reproduce.bash
/bin/bash
GNU bash, version 4.2.37(1)-release (x86_64-pc-linux-gnu)
setm.bash
x
x
x
x
x
setm-bad.bash
x
x
x
x
x
=====
/home/dualbus/local/bin/bash
GNU bash, version 4.3.0(1)-rc2 (x86_64-unknown-linux-gnu)
setm.bash
x
x
x
x
x
setm-bad.bash
x
x
x
=====
/home/dualbus/bb/prefix/bin/bash
GNU bash, version 4.3.0(1)-maint (x86_64-unknown-linux-gnu)
setm.bash
x
x
x
x
x
setm-bad.bash
x
x
x
x
x
=====
The bb/prefix version is the devel branch after applying the attached
patch.
As you can notice, bash 4.3 exits earlier. It should do 5 iterations,
but instead, it only completes 3. I found that is has something to do
with using queue_sigchld_trap instead of run_sigchld_trap, which I
assume fixes another issue, but the fix introduced this error.
--
Eduardo A. Bustamante López
diff --git a/jobs.c b/jobs.c
index 4982019..35f3f9d 100644
--- a/jobs.c
+++ b/jobs.c
@@ -3346,6 +3346,9 @@ itrace("waitchld: waitpid returns %d block = %d", pid, block);
if (sigchld == 0)
longjmp (wait_intr_buf, 1);
}
+ else
+ run_sigchld_trap (children_exited); /* XXX */
+#if 0
/* If not in posix mode and not executing the wait builtin, queue the
signal for later handling. Run the trap immediately if we are
executing the wait builtin, but don't break out of `wait'. */
@@ -3357,6 +3360,7 @@ itrace("waitchld: waitpid returns %d block = %d", pid, block);
run_sigchld_trap (children_exited); /* XXX */
else
queue_sigchld_trap (children_exited);
+#endif
}
/* We have successfully recorded the useful information about this process
