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
CONFORMING TO
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), sigaltstack(2), signal(2), signal(7)
COLOPHON
This page is part of release 3.24 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/.