<ucontext.h>(0P)                                    POSIX Programmer's Manual                                   <ucontext.h>(0P)



NAME
       ucontext.h - user context

SYNOPSIS
       #include <ucontext.h>

DESCRIPTION
       The <ucontext.h> header shall define the mcontext_t type through typedef.

       The  <ucontext.h>  header  shall define the ucontext_t type as a structure that shall include at least the following mem-
       bers:


              ucontext_t *uc_link     Pointer to the context that is resumed
                                      when this context returns.
              sigset_t    uc_sigmask  The set of signals that are blocked when this
                                      context is active.
              stack_t     uc_stack    The stack used by this context.
              mcontext_t  uc_mcontext A machine-specific representation of the saved
                                      context.

       The types sigset_t and stack_t shall be defined as in <signal.h> .

       The following shall be declared as functions and may also be defined as macros, Function prototypes shall be provided.


              int  getcontext(ucontext_t *);
              int  setcontext(const ucontext_t *);
              void makecontext(ucontext_t *, void (*)(void), int, ...);
              int  swapcontext(ucontext_t *restrict, const ucontext_t *restrict);

       The following sections are informative.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       <signal.h>, the System Interfaces volume of  IEEE Std 1003.1-2001,  getcontext(),  makecontext(),  sigaction(),  sigproc-
       mask(), sigaltstack()

COPYRIGHT
       Portions  of  this  text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for
       Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6,  Copy-
       right (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any
       discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open  Group
       Standard   is   the   referee   document.   The   original   Standard   can   be   obtained  online  at  http://www.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                              <ucontext.h>(0P)