Hello, the „-w“ parameter is meant for specifying the working directory. Usually the system specific init scipts are setup in a way to allow Kamailio to write to a proper directory where it is can place files. So, it can be flexible configured as necessary. About code extensions – have not looked into that particular function right now, but pull requests can be always created and will be reviewed by the developers. Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com *From:* sr-users &lt;sr-users-bounces(a)lists.kamailio.org&gt; *On Behalf Of *Leonid Fainshtein *Sent:* Wednesday, September 30, 2020 6:01 PM *To:* Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt; *Subject:* Re: [SR-Users] Kamailio fails to start when tls module parameter 'config' contains a folder name Actually, it is possible to use the libc 'P_tmpdir' macro in order to get the temporary folder name. Best regards, Leonid Fainshtein On Wed, Sep 30, 2020 at 6:35 PM Leonid Fainshtein < leonid.fainshtein(a)xorcom.com&gt; wrote: Hi, I am using Kamailio 5.4.1 installed from the packages on Ubuntu 18.04. When I define 'modparam("tls", "config", "<folder>")', Kamailio fails to start: ERROR: tls [tls_config.c:418]: tls_load_config(): cannot make tmp file configrcCczj ERROR: <core> [core/sr_module.c:849]: init_mod(): Error while initializing module tls (/usr/lib/x86_64-linux-gnu/kamailio/modules/tls.so) I checked the tls_load_config() function and found that when a folder is defined in the 'config' parameter, the function tries to open a temporary file in the working directory. I believe that the working directory at that point is the folder where Kamailio was started: /usr/sbin. I succeeded to launch Kamailio in two ways: Method 1: copy 'kamailio' to /tmp and modify kamalio.service accordingly. This experiment result made me think that the working folder is the folder where kamailio is started. Method 2: add Kamailio command line parameter "-w /tmp" (I also tried to define the Systemd 'WorkingDirectory' parameter but it didn't have any effect.) I think that the ultimate solution for this problem is to modify the tls_load_config() function in such a way that it will open the temporary file in a folder that is intended for the temporary files. For example, the /tmp folder in Linux and *BSD systems. I guess that /tmp is a good place in MacOS as well. Best regards, Leonid Fainshtein