wip

usage.c

@@ -0,0 +1,22 @@
+#include "usage.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static void report(const char* prefix, const char *err, va_list params)
+{
+  char msg[4096];
+  vsnprintf(msg, sizeof(msg), err, params);
+  fprintf(stderr, "%s%s\n", prefix, msg);
+}
+
+void die(const char* err, ...)
+{
+  va_list params;
+
+  va_start(params, err);
+  report("fatal: ", err, params);
+  va_end(params);
+  exit(128);
+}