diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index f8603070..267e5896 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -292,6 +292,16 @@ tm_format_date(char *x, bird_clock_t t)
   sprintf(x, "%02d-%02d-%04d", tm->tm_mday, tm->tm_mon+1, tm->tm_year+1900);
 }
 
+void
+tm_format_datetime(char *x, bird_clock_t t)
+{
+  struct tm *tm;
+
+  tm = localtime(&t);
+  if (strftime(x, TM_DATETIME_BUFFER_SIZE, "%d-%m-%Y %H:%M:%S", tm) == TM_DATETIME_BUFFER_SIZE)
+    strcpy(x, "<too-long>");
+}
+
 void
 tm_format_reltime(char *x, bird_clock_t t)
 {
diff --git a/sysdep/unix/timer.h b/sysdep/unix/timer.h
index 242b330b..b33622aa 100644
--- a/sysdep/unix/timer.h
+++ b/sysdep/unix/timer.h
@@ -35,8 +35,10 @@ extern bird_clock_t now;		/* Time in seconds since unknown epoch */
 bird_clock_t tm_parse_date(char *);	/* Convert date to bird_clock_t */
 void tm_format_date(char *, bird_clock_t);	/* Convert bird_clock_t to date */
 #define TM_DATE_BUFFER_SIZE 12		/* Buffer size required by tm_format_date */
+void tm_format_datetime(char *, bird_clock_t);	/* Convert bird_clock_t to date + time */
+#define TM_DATETIME_BUFFER_SIZE 64	/* Buffer size required by tm_format_datetime */
 void tm_format_reltime(char *, bird_clock_t);	/* Convert bird_clock_t to relative datetime string */
-#define TM_RELTIME_BUFFER_SIZE 12	/* Buffer size required by tm_format_time */
+#define TM_RELTIME_BUFFER_SIZE 12	/* Buffer size required by tm_format_reltime */
 
 #ifdef TIME_T_IS_64BIT
 #define TIME_INFINITY 0x7fffffffffffffff