[patch v2] manual: Update signal descriptions

[Florian Weimer]

* DJ Delorie:

> index 2012980efe..a9cf34c459 100644
> --- a/manual/signal.texi
> +++ b/manual/signal.texi
> @@ -427,9 +427,18 @@ failure to properly emulate them.
>  
>  @deftypevr Macro int  SIGSYS
>  @standards{Unix, signal.h}
> -Bad system call; that is to say, the instruction to trap to the
> -operating system was executed, but the code number for the system call
> -to perform was invalid.
> +System call event.  This signal may be generated by a valid system
> +call which requested an invalid sub-function, and also by the SECCOMP
> +filter when it filters a system call.

Suggest: when it filters [or traps] a system call

See SECCOMP_RET_TRAP.

With Stefan's last comments, I consider my ctrl-alt-del questions
resolves.

So consider making that seccomp adjustment, and then:

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Thanks,
Florian