fn progressParentFile(userdata: ?*anyopaque) std.Progress.ParentFileError!File
fn progressParentFile(userdata: ?*anyopaque) std.Progress.ParentFileError!File { const ev: *Evented = @ptrCast(@alignCast(userdata)); const cancel_protection = swapCancelProtection(ev, .blocked); defer assert(swapCancelProtection(ev, cancel_protection) == .blocked); ev.scanEnviron() catch |err| switch (err) { error.Canceled => unreachable, // blocked }; return ev.environ.zig_progress_file; }