NAME¶
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.
RETURN VALUE¶
sigreturn() never returns.
FILES¶
/usr/src/linux/arch/i386/kernel/signal.c
/usr/src/linux/arch/alpha/kernel/entry.S
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.
SEE ALSO¶
kill(2),
restart_syscall(2),
sigaltstack(2),
signal(2),
signal(7)
COLOPHON¶
This page is part of release 3.74 of the Linux
man-pages project. A
description of the project, information about reporting bugs, and the latest
version of this page, can be found at
http://www.kernel.org/doc/man-pages/.
