(unless you are talking about the 'first' save) it should be simply

[menusave(
|
[s pd-mypatch.pd]

I've never found a way of saving the patch to the current file, but if you want to save it to a new file, you can do this:

Did not how 'savetofile' worked until you mentioned it! Thanks!! I think this should do it:

[savetofile mypatch.pd /path/to/file(
|
[s pd-mypatch.pd]