Fix bug in io.c:wait_any where we may not have waited for the requested child process exit status.

2 files changed, 13 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index eb7555f2..f0c3dc4e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-01-05         Andrew J. Schorr     <aschorr@telemetry-investments.com>
+
+	* io.c (wait_any): If the `interesting' argument is non-zero, then we
+	must not return until that child process has exited, since the caller
+	gawk_pclose depends on our returning its exit status.  So in that case,
+	do not pass WNOHANG to waitpid.
+
 2015-01-04         Andrew J. Schorr     <aschorr@telemetry-investments.com>
 
 	* gawkapi.h: Fix another comment typo.
diff --git a/io.c b/io.c
index 6e6d1a1a..f849f839 100644
--- a/io.c
+++ b/io.c
@@ -2250,7 +2250,12 @@ wait_any(int interesting)	/* pid of interest, if any */
 #endif
 	for (;;) {
 # if defined(HAVE_WAITPID) && defined(WNOHANG)
-		if ((pid = waitpid(-1, & status, WNOHANG)) == 0)
+		/*
+		 * N.B. If the caller wants status for a specific child process
+		 * (i.e. interesting is non-zero), then we must hang until we
+		 * get exit status for that child.
+		 */
+		if ((pid = waitpid(-1, & status, (interesting ? 0 : WNOHANG))) == 0)
 			/* No children have exited */
 			break;
 # elif defined(HAVE_SYS_WAIT_H)	/* POSIX compatible sys/wait.h */