I've noticed this in a few games i bought on GOG. Most recently it's in Wastelands 2 DC. steam_api.dll (or maybe some other steam related file) is included in the install. Why is there such a file? Is it a real full working steam file or just some placeholder because the game was originally released on steam and looks for such a file? Is it even legal for gog to have steam files (or maybe dummy files with steam name) or is there a risk this might cause them troubles? Does the gog team knows some of their games come with steam stuff?

Lots of questions, i know, but this has bothered me ever since i noticed it. There was even one game that had a link on the main menu to get their DLC on steam (i think it was Eador : masters of the broken wolrd)

In essence, yes. It's not quite as simple as a placeholder (it's the actual steam_api.dll as far as I can tell), but it is inert. The game is essentially designed to use Steam but to work as best it can without it. It expects the DLL to be present either way, but well-written games will know how to handle it if the Steam service is not "available". Lazily-written games just bomb out if the Steam service can't be found.

The game calls the Steam API through steam_api.dll and performs various functions through this, such as acquiring the current Steam account and user name. It's ironically actually the Steam API's functions that tell the game that the Steam service isn't available. How the developer handles the lack of Steam service from that point is up to them. If they're completely lazy, they can just have the game terminate unceremoniously. If they're slightly lazy, they can have error messages pop up in the game but have the game work anyway. If they're clever, they can actually have the Steam features hidden from view if the Steam service cannot be initialised (I believe Anomaly 2 does this). Yes, they know of its presence. As regards the legality of it, that's down to the individual developer/publisher, but I don't think Valve really has a problem with it. If it makes you feel any better, there are games on Steam that contain GOG's proprietary software (mostly Square Enix back catalogue titles that have been ripped straight from the GOG versions, but I believe there are others there as well - some DOSBox games in particular). Yes, a few games have had the problem of blatant Steam references. Brütal Legend actually points out that Steam isn't running whenever you try to start multiplayer mode.

FYI. there are games on Steam with GOG components in them.

It's a very confusing world in which we live.

Who wants pie? :D

Yes totally agree. But once infected even inert as the term is, its a total pig to get rid of. Hence developers who put so much effort into getting it into their software, don't have the resources to build a version without it (if that sounds daft, and you say why bother in the first place, me too). Hence we are stuck with it. Just make sure you play any games from the stores with internet connection removed, no telling whats happening behind the scenes (Win10 looking at you, VVran and VanHelsing checking for "news" items etc.).

Gabe is eating... err, watching you!

It's because steam is out to get you and take over your machine. Those DLLs are watching you.

O.o

What kind of pie? It better not be cream. :O

Pewdie pie.

I'm pretty sure that steam_api.dll is part of the SDK Redistributables that 1.1b of this license grants the licensee a right to distribute with their software. So, shouldn't be a problem.

Unfortunately, 3.2 pretty much states that Valve may revoke this at any time if they feel like it...

Why are we talking about this file like it is a disease? If it doesn't do anything why care?

it is the DRM part that ties a game to Steam , I own a few games on steam and I removed that steam api thing and the game worked without steam being installed on my pc after I removed it and some games break when you remove it as well.

and sometimes some games like batman asylum work even if you don't remove it. guess it is how hard they implement it i guess.

Well, that's really the topic for debate isn't it. Has it conclusively, I mean can I have it in writing signed in witness of a lawyer, been proved to not do anything - and I mean anything. I personally have zero trust in anything steam, from their client through to sites selling game keys. Add to that I spend a lot of time cleaning my machine, keeping it in good order etc. so I don't want things fecking it up. To be honest I already pull out the internet connection anytime I not using the web, which is how I picked up on VVran and van Helsing to name two, who were caught attempting to phone home - and no I don't care if it was just news, they attempted to connect to the internet without asking me.
I barely trust my own mum you see :o)

Yeah, I don't trust your mom either.

I will tell her that, it will be double price for you next time!!