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PtFdProcF_t, PtFdProc_t

Type for defining a file-descriptor function


typedef int PtFdProcF_t( int fd,
                         void *data,
                         unsigned mode );

typedef PtFdProcF_t *PtFdProc_t;


These data types define pointers to file-descriptor functions. The PtFdProcF_t type is the function type that the PtFdProc_t type points to. This allows you to do something like this:

PtFdProcF_t my_fd_proc;

int my_fd_proc( int fd, void *data unsigned mode) {

The compiler should detect any inconsistencies between the two declarations of my_fd_proc() and give you an error (which is better than a “pointer mismatch” warning on the call to PtAppAddFd()).



See also:


Other I/O mechanisms in the Interprocess Communication chapter of the Photon Programmer's Guide