Function:     ScheduleWrite

Purpose:      Register a function to be called  whenever data can be written
              to a specified file descriptor.

Category:     SYSTEM

File:         events.src

Author:       J.P. Terlouw

Use:          #include "events.h"
              ident id;
              id = ScheduleWrite(proc, fd, arg);

              void(*proc)()   -  pointer to function.
              int fd          -  file descriptor.
              void *arg       -  'client' data

Description:  ScheduleWrite registers a function to be called by MainLoop
              whenever data can be written to file descriptor 'fd'.
              In this call, 'arg' will be passed to 'proc'.
              The return value is a unique identification code corresponding
              with the registration, which will also be passed as an
              argument to 'proc'.

              The prototype of 'proc' is:
                  void proc(ident id, int fd, void *arg);

              This function can be used when the calling program should not
              "block" when data cannot immediately be written, e.g., when
              writing a large amount of data to a socket when it is not sure
              that the receiving process immediately can accept it.

Related Docs: events.dc3, ScheduleRead.dc3, ScheduleTimer.dc3, Deschedule.dc3,
              DescheduleAll.dc3, MainLoop.dc2, AttachXt.dc2.

Updates:      Apr 8, 1997: JPT Document created.