mrkgnao: I agree.
That's not what B1tF1ghter and I were talking about, though. We were talking the need for a custom piece of software for installation, as far as I understand.
Anyhow, for me, in practical terms, the difference between the GOG offline installer and SteamCmd is simply one of storage space saving. As soon as I buy a game on GOG, I download the offline installer and back it up. As soon as I buy a game on Steam, I download and install and back it up using SteamCmd. In both cases, I end with a DRM-free game available offline from that point on, except that on GOG the game is compressed to some degree, whereas on Steam it's fully installed. So the only real difference is wasted storage space on Steam. I can live with that.
Truth007: What is SteamCmd?
SteamCMD is an official Valve-made tool.
It was created for (MEANT for) multiplayer server admins *.
It runs entirely from console/terminal.
You can (among other things):
- download depots
- install / upgrade software
- download workshop content
- manage mp servers (to a degree)
- fetch data with usual Steam API commands
- requesting product licenses (not something average Steam user would be interested in doing by hand)
Plus many others.
But most of usual Steam functionality is trimmed out.
It supports scripting, as well as "anonymous" login, latter allowing downloding some depots (not a whole lot).
* Technically speaking you can download singleplayer games this way.
But it wasn't intended purpose, still, many people do use it that way.
Also, btw, there *might* be a way to LAUNCH games with SteamCMD (I gathered this impression from extensive read-ups of documentation) but personally I had no success trying to do so.