+#define USIGN_EXEC "/usr/bin/usign"
+
+/*
+ * check for revoker deadlink in pubkeydir
+ * return true if a revoker exists, false otherwise
+ */
+int _usign_key_is_revoked(const char *fingerprint, const char *pubkeydir) {
+ char tml[64] = {0};
+ char rfname[256] = {0};
+
+ snprintf(rfname, sizeof(rfname)-1, "%s/%s", pubkeydir, fingerprint);
+ if (readlink(rfname, tml, sizeof(tml)) > 0 &&
+ !strcmp(tml, ".revoked.")) {
+ return true;
+ };
+
+ return false;
+}
+
+#ifdef UCERT_FULL
+/*
+ * call usign -S ...
+ * return WEXITSTATUS or -1 if fork or execv fails
+ */