Look for all machines with name "x"

[ficolas]

Well so I need to ejecute a lua code where every machine X is placed
I asked this, and kovarex said that I can use the findentity function, but that this will be slow, How do I use this?
Also, I can use the onplace event, to record the position of the machine on a file, using the file API, but in order to do this, ill need to check if the entity is still there, I could use isvalid, but that wont say that the name is "x", it will only say that there is an entity.

[kovarex]

You can manage the list of all entities created by player by catching events oncreated, onmined and onbuild ...

[ficolas]

I think the onmined event isnt at the wiki