win32: add env var to control error dialogs

If the environment variable BB_CRITICAL_ERROR_DIALOGS is set to
1 critical error dialogs are enabled.  If unset or set to any
other value they aren't.  In either case the error messages
introduced by commit 790e37727 (win32: revert 'don't set error
mode') are issued.

The shell exports BB_CRITICAL_ERROR_DIALOGS to the environment
immediately on any change so the setting takes effect at once.

Adds 104-160 bytes.

(GitHub issue #423)

1 files changed, 6 insertions, 0 deletions

diff --git a/win32/mingw.c b/win32/mingw.c
index 4398f5462..49e1bcfa4 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -2507,3 +2507,9 @@ windows_env(void)
         }
         return FALSE;
 }
+
+void FAST_FUNC
+change_critical_error_dialogs(const char *newval)
+{
+        SetErrorMode(strcmp(newval, "1") == 0 ? 0 : SEM_FAILCRITICALERRORS);
+}