Here is a list of all documented variables with links to the struct/union documentation for each field:

A

B

C

D

E

I

K

L

M

O

P

R

S

T

V

X

- x -

• x_common : sip_session_expires_s
• x_delta : sip_session_expires_s
• x_next : sip_session_expires_s
• x_params : sip_session_expires_s
• x_refresher : sip_session_expires_s