[t:2499] Set errno so that brtloader's bl_fwrite() function gets correct error...

[t:2499] Set errno so that brtloader's bl_fwrite() function gets correct error return if the real fwrite() produces an error.

git-svn-id: file:///svn/toku/tokudb@19934 c7de825b-a66e-492c-adef-691d508d4ae1

src/tests/loader-cleanup-test.c

@@ -93,6 +93,9 @@ static size_t bad_fwrite (const void *ptr, size_t size, size_t nmemb, FILE *stre
 	r = -1;
     } else {
 	r = fwrite(ptr, size, nmemb, stream);
+	if (r!=nmemb) {
+	    errno = ferror(stream);
+	}
     }
     return r;
 }