+/************************************************/
+
+static FILE *
+expand_open(const uschar * filename,
+ const uschar * varname, const uschar * reason)
+{
+const uschar * s = expand_cstring(filename);
+FILE * fp = NULL;
+
+if (!s || !*s)
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "Failed to expand %s: '%s'\n", varname, filename);
+else if (*s != '/' || is_tainted(s))
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "%s is not %s after expansion: '%s'\n",
+ varname, *s == '/' ? "untainted" : "absolute", s);
+else if (!(fp = Ufopen(s, "rb")))
+ log_write(0, LOG_MAIN|LOG_PANIC, "Failed to open %s for %s "
+ "message texts: %s", s, reason, strerror(errno));
+return fp;
+}
+