diff --git a/src/tls.c b/src/tls.c
index 6e40e3774..6dc3de505 100644
--- a/src/tls.c
+++ b/src/tls.c
@@ -114,7 +114,7 @@ void verify_cert_expiry(int idx) {
   if ((x509 = SSL_CTX_get0_certificate(ssl_ctx)) &&
       (ASN1_TIME_cmp_time_t(X509_get0_notAfter(x509), time(NULL)) < 0)) {
     if (idx)
-        dprintf(idx,"WARNING: certificate expired: %s\n", tls_certfile);
+        dprintf(idx, "WARNING: certificate expired: %s\n", tls_certfile);
     else
       putlog(LOG_MISC, "*", "WARNING: certificate expired: %s", tls_certfile);
   }