diff --git a/lib/libc/gen/popen.c b/lib/libc/gen/popen.c
index 89aba1638ed9..c6b303e5e64d 100644
--- a/lib/libc/gen/popen.c
+++ b/lib/libc/gen/popen.c
@@ -35,7 +35,8 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)popen.c	8.1 (Berkeley) 6/4/93";
+/* static char sccsid[] = "@(#)popen.c	8.1 (Berkeley) 6/4/93"; */
+static char *rcsid = "$Id: popen.c,v 1.9 1994/05/09 16:28:27 jtc Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -64,8 +65,10 @@ popen(program, type)
 	FILE *iop;
 	int pdes[2], pid;
 
-	if (*type != 'r' && *type != 'w' || type[1])
+	if (*type != 'r' && *type != 'w' || type[1]) {
+		errno = EINVAL;
 		return (NULL);
+	}
 
 	if ((cur = malloc(sizeof(struct pid))) == NULL)
 		return (NULL);
@@ -96,7 +99,7 @@ popen(program, type)
 			}
 			(void)close(pdes[1]);
 		}
-		execl(_PATH_BSHELL, "sh", "-c", program, NULL);
+		execl(_PATH_BSHELL, "sh", "-c", program, (char *) 0);
 		_exit(127);
 		/* NOTREACHED */
 	}
@@ -129,8 +132,7 @@ pclose(iop)
 	FILE *iop;
 {
 	register struct pid *cur, *last;
-	int omask;
-	union wait pstat;
+	int pstat;
 	pid_t pid;
 
 	(void)fclose(iop);
@@ -142,12 +144,9 @@ pclose(iop)
 	if (cur == NULL)
 		return (-1);
 
-	/* Get the status of the process. */
-	omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
 	do {
-		pid = waitpid(cur->pid, (int *) &pstat, 0);
+		pid = waitpid(cur->pid, &pstat, 0);
 	} while (pid == -1 && errno == EINTR);
-	(void)sigsetmask(omask);
 
 	/* Remove the entry from the linked list. */
 	if (last == NULL)
@@ -156,5 +155,5 @@ pclose(iop)
 		last->next = cur->next;
 	free(cur);
 		
-	return (pid == -1 ? -1 : pstat.w_status);
+	return (pid == -1 ? -1 : pstat);
 }