sigreturn —
return from signal
int
sigreturn(
struct
sigcontext *scp);
The
sigreturn() syscall is used by the signal
handling facility to atomically switch stacks, restore registers and the
thread's signal mask, and return from a signal context to resume the
processing that was interrupted by the signal.
Note that sigcontext contains machine dependent information.
Direct use of
sigreturn is no longer
supported and it is not provided as a function. As used in the signal
trampoline provided by the system, if
sigreturn fails and returns then the
process is terminated.
If successful, the system call does not return. Otherwise, a value of -1 is
returned and
errno is set to indicate the
error.
sigreturn() will fail and the process context
will remain unchanged if one of the following occurs.
-
-
- [
EFAULT]
- scp points to memory that is not a valid
part of the process address space.
-
-
- [
EINVAL]
- The sigcontext provided is invalid or would improperly raise the privilege
level of the process.
sigaction(2),
setjmp(3)
The
sigreturn() function appeared in
4.3BSD. The function was removed from libc in
OpenBSD 6.0.
![[OpenBSD]](/openbsd.gif){kind=small}