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), restart_syscall(2), sigaltstack(2), signal(2), signal(7)

COLOPHON

       This page is part of release 3.54 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/.