Improve call-process-region error message.

* src/callproc.c (Fcall_process_region): Include directory component
in mkstemp error message.

Fixes: debbugs:11586

1 files changed, 1 insertions, 1 deletions

diff --git a/src/callproc.c b/src/callproc.c
index f7c9971907d..976d3061c8b 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -1015,7 +1015,7 @@ usage: (call-process-region START END PROGRAM &optional DELETE BUFFER DISPLAY &r
       UNBLOCK_INPUT;
       if (fd == -1)
         report_file_error ("Failed to open temporary file",
-                           Fcons (Vtemp_file_name_pattern, Qnil));
+                           Fcons (build_string (tempfile), Qnil));
       else
         close (fd);
     }