POSIX: don't spawn zombies.

chrome/browser/browser_main.cc

Index: chrome/browser/browser_main.cc
diff --git a/chrome/browser/browser_main.cc b/chrome/browser/browser_main.cc
index d687acbba459efa31ecb6333ff2173a829c46591..a2a5530f5dad29fed01b87a3b7a245ac25b82126 100644
--- a/chrome/browser/browser_main.cc
+++ b/chrome/browser/browser_main.cc
@@ -56,6 +56,7 @@
 // TODO(port): get rid of this include. It's used just to provide declarations
 // and stub definitions for classes we encouter during the porting effort.
 #include "chrome/common/temp_scaffolding_stubs.h"
+#include <signal.h>
 #endif
 
 // TODO(port): several win-only methods have been pulled out of this, but
@@ -180,6 +181,12 @@ void RunUIMessageLoop(BrowserProcess* browser_process) {
 #endif
 }
 
+#if defined(OS_POSIX)
+// See comment below, where sigaction is called.
+void SIGCHLDHandler(int signal) {
+}
+#endif
+
 }  // namespace
 
 // Main routine for running as the Browser process.
@@ -201,6 +208,14 @@ int BrowserMain(const MainFunctionParams& parameters) {
   tracked_objects::AutoTracking tracking_objects;
 #endif
 
+#if defined(OS_POSIX)
+  // We need to accept SIGCHLD, even though our handler is a no-op because
+  // otherwise we cannot wait on children. (According to POSIX 2001.)
+  struct sigaction action = {0};
+  action.sa_handler = SIGCHLDHandler;
+  CHECK(sigaction(SIGCHLD, &action, NULL) == 0);
+#endif
+
   // Do platform-specific things (such as finishing initializing Cocoa)
   // prior to instantiating the message loop. This could be turned into a
   // broadcast notification.