siginfo_fields_union

const siginfo_fields_union = extern union {
    pad: [128 - 2 * @sizeOf(c_int) - @sizeOf(c_long)]u8,
    common: extern struct {
        first: extern union {
            piduid: extern struct {
                pid: pid_t,
                uid: uid_t,
            },
            timer: extern struct {
                timerid: i32,
                overrun: i32,
            },
        },
        second: extern union {
            value: sigval,
            sigchld: extern struct {
                status: i32,
                utime: clock_t,
                stime: clock_t,
            },
        },
    },
    sigfault: extern struct {
        addr: *allowzero anyopaque,
        addr_lsb: i16,
        first: extern union {
            addr_bnd: extern struct {
                lower: *anyopaque,
                upper: *anyopaque,
            },
            pkey: u32,
        },
    },
    sigpoll: extern struct {
        band: isize,
        fd: i32,
    },
    sigsys: extern struct {
        call_addr: *anyopaque,
        syscall: i32,
        native_arch: u32,
    },
}