ucontext(5)                                              ucontext(5)


       NAME
             ucontext - user context

       SYNOPSIS
             #include <ucontext.h>

       DESCRIPTION
             The ucontext structure defines the context of a thread of
             control within an executing process.

             This structure includes at least the following members:

                   ucontext_t  *uc_link
                   sigset_t    uc_sigmask
                   stack_t     uc_stack
                   mcontext_t  uc_mcontext

             uc_link is a pointer to the context that is to be resumed when
             this context returns.  If uc_link is equal to 0, then this
             context is the main context, and the process exits when this
             context returns.  The uc_link field is only meaningful for
             contexts created using makecontext.

             uc_sigmask defines the set of signals that are blocked when
             this context is active [see sigprocmask(2)].

             uc_stack defines the stack used by this context [see
             sigaltstack(2)].

             uc_mcontext contains the saved set of machine registers and
             any implementation specific context data.  Portable
             applications should not modify or access uc_mcontext.

       REFERENCES
             getcontext(2), makecontext(3C), sigaction(2), sigaltstack(2),
             sigprocmask(2)












                           Copyright 1994 Novell, Inc.               Page 1