ucontext(5)            MISC. FILE FORMATS             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:

          ucontextt  uclink
          sigsett    ucsigmask
          stackt     ucstack
          mcontextt  ucmcontext

     uclink is a pointer to the context that to be resumed  when
     this  context  returns.  If uclink is equal to 0, then this
     context is the main context, and the process exits when this
     context returns.

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

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

     ucmcontext contains the saved set of machine registers  and
     any implementation specific context data.  Portable applica-
     tions should not modify or access ucmcontext.

SEE ALSO
     getcontext(2), sigaction(2), sigprocmask(2), sigaltstack(2),
     makecontext(3C).




















                                                                1