Hook BSD err(), errx(), warn(), warnx(), etc. functions.

err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx() are
hooked.

tests/example_err.c

@@ -0,0 +1,51 @@
+/*
+ * Test err(), verr(), ... Non-standard, BSD only.
+ *
+ * Copyright (C) 2013  Simon Ruderich
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../src/compiler.h"
+#include "example.h"
+
+
+int main(int argc unused, char **argv unused) {
+    pid_t pid;
+
+    FORKED_TEST(pid) { errno = ENOMEM; err(0, "error: %s", "message"); }
+    FORKED_TEST(pid) { errno = ENOMEM; err(1, "error: %s", "message"); }
+
+    FORKED_TEST(pid) { errx(0, "error: %s", "message"); }
+    FORKED_TEST(pid) { errx(1, "error: %s", "message"); }
+
+    errno = ENOMEM;
+    warn("warning: %s", "message");
+    warnx("warning: %s", "message");
+
+    /* v*() functions are implicitly tested - the implementation uses them. */
+
+    printf("\n");
+    return EXIT_SUCCESS;
+}