Is this function available in user Strategies? If so, how does it work? Where or How do I set the "name" string of each trade?

I want: efficient lookups of entered trades by unique identifier, regardless of trade status (open, pending, closed). So far I maintain a data structure containing all known TRADE* memory addresses, but this seems fragile.

It is undocumented, but should work as expected - the name parameter is the algo ID. It returns the first found trade AFAIK.

The official way to look for a trade is enumerating all trades.