diff --git a/asyncqueue.c b/asyncqueue.c
index 90e86dce..6e9caf0c 100644
--- a/asyncqueue.c
+++ b/asyncqueue.c
@@ -570,7 +570,7 @@ int AsyncQueueAction(SConnection *pCon, SicsInterp *pSics,
       int i, j;
       cmd[0] = '\0';
       for (i = 2; i < argc; ++i) {
-        j = snprintf(&cmd[idx], 10240 - j, "%s%s",
+        j = snprintf(&cmd[idx], 10240 - idx, "%s%s",
             (i > 2) ? " " : "",
             argv[i]);
         if (j < 0)