"X-Kannel-DLR-Mask" value

[Andrikopoulos Dimitrios]

Hello,

As I don't know C, can someone tell me what the following code line
means for the value of the header
"X-Kannel-DLR-Mask"?
 
http_header_add(push_headers, "X-Kannel-DLR-Mask", octstr_get_cstr(dos =
octstr_format("%d", 31)));

If possible provide equivalent code for Perl or PHP
 
Thanks,
Dimitris