Work around a Windows oddity when a pipe with no reader is written to.

The first WriteFile() returns ERROR_BROKEN_PIPE, subsequent WriteFile()s
return ERROR_NO_DATA, which is not translated to EPIPE, but EINVAL.

Hmpf!

write_or_die.c

@@ -34,7 +34,16 @@ void maybe_flush_or_die(FILE *f, const char *desc)
 			return;
 	}
 	if (fflush(f)) {
+#ifndef __MINGW32__
 		if (errno == EPIPE)
+#else
+		/*
+		 * On Windows, EPIPE is returned only by the first write()
+		 * after the reading end has closed its handle; subsequent
+		 * write()s return EINVAL.
+		 */
+		if (errno == EPIPE || errno == EINVAL)
+#endif
 			exit(0);
 		die("write failure on %s: %s", desc, strerror(errno));
 	}