Block SIGCHLD during system() call (per POSIX)

diff --git a/pp_sys.c b/pp_sys.c
index 92624bf..c7212b3 100644 (file)
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -4116,9 +4116,17 @@ PP(pp_system)
        Pid_t childpid;
        int pp[2];
        I32 did_pipes = 0;
+#if (defined(HAS_SIGPROCMASK) && !defined(PERL_MICRO))
+       sigset_t newset, oldset;
+#endif
 
        if (PerlProc_pipe(pp) >= 0)
            did_pipes = 1;
+#if (defined(HAS_SIGPROCMASK) && !defined(PERL_MICRO))
+       sigemptyset(&newset);
+       sigaddset(&newset, SIGCHLD);
+       sigprocmask(SIG_BLOCK, &newset, &oldset);
+#endif
        while ((childpid = PerlProc_fork()) == -1) {
            if (errno != EAGAIN) {
                value = -1;
@@ -4128,6 +4136,9 @@ PP(pp_system)
                    PerlLIO_close(pp[0]);
                    PerlLIO_close(pp[1]);
                }
+#if (defined(HAS_SIGPROCMASK) && !defined(PERL_MICRO))
+               sigprocmask(SIG_SETMASK, &oldset, NULL);
+#endif
                RETURN;
            }
            sleep(5);
@@ -4146,6 +4157,9 @@ PP(pp_system)
                result = wait4pid(childpid, &status, 0);
            } while (result == -1 && errno == EINTR);
 #ifndef PERL_MICRO
+#ifdef HAS_SIGPROCMASK
+           sigprocmask(SIG_SETMASK, &oldset, NULL);
+#endif
            (void)rsignal_restore(SIGINT, &ihand);
            (void)rsignal_restore(SIGQUIT, &qhand);
 #endif
@@ -4176,6 +4190,9 @@ PP(pp_system)
            XPUSHi(STATUS_CURRENT);
            RETURN;
        }
+#if (defined(HAS_SIGPROCMASK) && !defined(PERL_MICRO))
+       sigprocmask(SIG_SETMASK, &oldset, NULL);
+#endif
        if (did_pipes) {
            PerlLIO_close(pp[0]);
 #if defined(HAS_FCNTL) && defined(F_SETFD)