I installed steam on yet a third computer with archlinux and awesome and it had the same error. I installed Steam on my laptop and launched it, nothing in between, and it worked (plugged into ethernet). I installed it on this third machine and launched it, exactly the same, but 1) it had a very strange error where the text is displayed incorrectly (though I haven't looked into that issue yet, it's almost certainly unrelated) and it had the same error as on my main machine. My laptop has intel integrated graphics and an intel quad-core CPU (I could get the model if necessary) and the third machine has an AMD graphics card and an AMD FX-6300. Perhaps the issue is with AMD CPUs..? Either way, I do now know that it does not have to do with steamos-xpad, that it's a standalone issue
It appears there was just a client update a half hour ago (or less) and the problem now seems to be fixed on my desktop. The other 2 have the same error of missing libraries, but that's fair as they have fewer packages installed. Not sure if either of you were responsible for getting it fixed, but thank you!
Nothing extracted yet.
x86_64 Arch Linux, awesome window manager, NVIDIA GTX 1070 (proprietary drivers), AMD FX-8300
I tried installing steamos-xpad-dkms earlier today to try to get rumble working on my controller. I installed a few things to try to get it to work, including linux-lts, linux-lts-headers, steamos-xpad-dkms, dkms. Once I thought I had that setup, I went to go to steam to test it and it started logging in, stated "Connecting account: meplaysteem" and after a few seconds failed saying "Could not connect to Steam network." After that it closes the app (rather than opening in offline mode, which I find a bit odd). Launching steam from the console provides no information about the connectivity error, only "Installing breakpad exception handler for appid(steam)/version(1496897923). I tried uninstalling everything I had installed to backtrack and get it to work, and it didn't. I tried deleting all files under ~/.steam/steam besides steamapps, uninstalling steam through pacman, then reinstalling it. That logged me out, of course, but it didn't work. When I logged in it recognized the computer as a new computer and sent me an email with the verification code. That whole process worked and it got to the same stage as before. The error isn't to do with the network because I installed steam on my laptop (nearly identical basic setup, x86_64 arch, awesome wm) and it opened fine.
Steps for reproducing this issue: I really don't know, I'd frankly rather not break another build of steam in a way that I've been unable to fix.
EDIT: this machine has an FX-8300, not an FX-6300