ucontext_t includes the following members:
ucontext_t * uc_link
sigset_t uc_sigmask
stack_t uc_stack
mcontext_t uc_mcontext
The
uc_link
member points to the context that will be resumed after the function
specified when modifying a context using
makecontext(3)
has returned.
If
uc_link
is a null pointer, then the context is the main context,
and the process will exit with an exit status of 0 upon return.
The
uc_sigmask
member is the set of signals that are blocked when the context is
activated.
Further information can be found in
sigprocmask(2).
The
uc_stack
member defines the stack used by the context.
Further information can be found in
sigaltstack(2).
The
uc_mcontext
member defines the machine state associated with the context;
it may consist of general registers, floating point registers
and other machine-specific information.
Its description is beyond the scope of this manual page;
portable applications should not access this structure member.
)
and
swapcontext(
)
functions first appeared in
AT&T
System V.4 UNIX
.