gtpc2mjb | C/C++ Language Support User's Guide |
User-defined device driver functions are functions that users provide and the TPF system calls.
Types of user-defined device driver functions are defined in c$spif.h. To add a user-defined device driver, you must add a function of each of these types to the COMX library and add an entry initialized with pointers to those functions to the user device driver interface table (UDDTBL).
The following sections explain each type of function. The examples under these types use a device driver for the null file (/dev/null). The null file always succeeds on writes (discarding the output data), is always at the end-of-file on reads, and always has a size of 0.