Q.93B Driver Interface
The signalling API, called Q.2931 Call Control (qcc), consists of two sets of similar functions: one for applications running in the kernel and one for applications running in user space. Each set provides functions to build and parse Q.2931 signalling messages, which are required to set up and tear down connections.
One additional function assists applications in establishing appropriate connections to the Q.93B driver. q_ioc_bind associates a service access point (SAP) with the specified connection to the Q.93B driver. The driver uses the SAP to direct incoming messages to applications.
Establishing a Connection to the Q.93B Driver
Use the open(2) system call to obtain a file descriptor to the driver. After opening the driver, q_ioc_bind should be called, associating in the Q.93B driver a service access point (SAP) with this application. Finally, if the application is a kernel driver, it should be linked above the Q.93B driver, using the I_LINK or I_PLINK ioctl (refer to the streamio(7) man page for information about this ioctl).
Appendix C Application Programmer’s Interface 89
