fn flagApc(userdata: ?*anyopaque, _: *windows.IO_STATUS_BLOCK, _: windows.ULONG) align(apc_align) callconv(.winapi) void
fn flagApc(userdata: ?*anyopaque, _: *windows.IO_STATUS_BLOCK, _: windows.ULONG) align(apc_align) callconv(.winapi) void { const flag: *bool = @ptrCast(userdata); flag.* = true; }