Function:     atabort

Purpose:      Register procedure to be called whenever a user abort occurs.

Category:     SYSTEM

File:         srvreq.c

Author:       J.P. Terlouw

Use:          atabort( proc, data);
                      proc    : procedure to be called; type void(*)(void*).
                                if a null pointer is specified, any previous
                                registration is removed.
                      data    : data to be passed to proc; type void*.

              If atabort is called more than once, only the most
              recently registered procedure will be called, i.e. subsequent
              calls supersede previous ones.
              As user aborts are asynchronous events, special care is needed
              to avoid damaging things which are in an indeterminate state.
              To protect critical sections of code, the routines enterc_c and
              leavec_c can be used.

Limitations:  This procedure is only available from C.

Related documents:
              enterc.dc2 leavec.dc2 atfinis.dc2

Updates:      Nov 29, 1991: JPT, Document created.