old_mask          490 src/subshell/common.c     sigset_t sigchld_mask, old_mask;
old_mask          494 src/subshell/common.c     sigprocmask (SIG_BLOCK, &sigchld_mask, &old_mask);
old_mask          500 src/subshell/common.c     sigdelset (&old_mask, SIGCHLD);
old_mask          504 src/subshell/common.c         sigsuspend (&old_mask);
old_mask          515 src/subshell/common.c     sigprocmask (SIG_SETMASK, &old_mask, NULL);