diff --git a/src/os_unix.c b/src/os_unix.c
index 4cc9de7..cda5407 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -5214,11 +5214,11 @@
     job->jv_channel = channel;  /* ch_refcount was set above */
 
     /* child stdin, stdout and stderr */
-    if (!use_file_for_in)
+    if (!use_file_for_in && fd_in[0] >= 0)
 	close(fd_in[0]);
-    if (!use_file_for_out)
+    if (!use_file_for_out && fd_out[1] >= 0)
 	close(fd_out[1]);
-    if (!use_out_for_err && !use_file_for_err)
+    if (!use_out_for_err && !use_file_for_err && fd_err[1] >= 0)
 	close(fd_err[1]);
     if (channel != NULL)
     {