return from signal
() 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
is no longer
supported and it is not provided as a function. As used in the signal
trampoline provided by the system, if
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
() will fail and the process context
will remain unchanged if one of the following occurs.
- scp points to memory that is not a valid
part of the process address space.
- The sigcontext provided is invalid or would improperly raise the privilege
level of the process.
() function appeared in
. The function was removed from libc in