Fix for previous commit

main.c

@@ -83,13 +83,13 @@ int main(int argc, char* const* argv)
       pid_child = pid;
       if (sigaction(SIGTERM, &forward_signal_descriptor, NULL) == -1)
         {
-          int err = errno;
+          int saved_errno = errno;
           // Have to kill child here, otherwise that gets orphaned and runs anyway.
           // Use SIGKILL here because it might forward SIGTERM to its child and that
           // decides not to stop.
           kill(pid_child, SIGKILL);
           // Restore errno as it might've been overwritten by kill
-          errno = err;
+          errno = saved_errno;
           err(errno, "Unable to set up signal handler in head process");
         }
       // parent waits for child then exits