sigreturn - return from signal handler and cleanup stack frame
SYNOPSIS
int sigreturn(unsigned long __unused);
DESCRIPTION
When the Linux kernel creates the stack frame for a signal handler, a
call to
sigreturn()
is inserted into the stack frame so that upon
return from the signal handler,
sigreturn()
will be called.
This
sigreturn()
call undoes everything that was
done---changing the process's signal mask, switching stacks (see
sigaltstack(2))---in
order to invoke the signal handler:
it restores the process's signal mask, switches stacks,
and restores the process's context (registers, processor flags),
so that the process directly resumes execution
at the point where it was interrupted by the signal.
sigreturn()
is specific to Linux and should not be used in programs intended to be
portable.
NOTES
The
sigreturn()
call is used by the kernel to implement signal handlers.
It should
never
be called directly.
Better yet, the specific use of the
__unused
argument varies depending on the architecture.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
