After chasing software issues for a couple of months, the problem with the audio on the gumstix was with the hardware. Gumstix issued an RMA and I have returned it to them for repair or replacement.
In the meantime, I’ve added Perl and nano to the gumstix and OpenSSH server to the Ubuntu machine. I have written a couple of Perl scripts and shell scripts and late yesterday I got the public/private key authentication set up between the gumstix and Ubuntu so I can run scripted secure file transfers.
I am discovering first hand what my older son means when he says that “Linux is only free if your time is worth nothing.” This is especially true for a newb trying to learn it from reading books and online. I don’t really know anyone who has experience in Linux except my older son who is 1) not here and 2) is busy with his own work and life. The key authentication is a case in point. The procedure is clear enough. Log on to the client account, generate the key pair, put the public key in the ~/.ssh/authorized_keys file on the user account on the server machine. I think it would have been that simple on two standard Linux computers. The gumstix uses dropbear instead of OpenSSH. I thought that was causing the problem. In the end it turned out that dropbearkey, the program that generates the key pair was not in the standard user path. I tried generating keys as root but (I now realize) that doesn’t work. While I could have changed the $PATH variable, I just specified the entire path when I ran dropbearkey. Then you need to specify the private key file when you log on…that isn’t standard in OpenSSH. Two days to figure that out. I’m learning…
If you live in a Linux world you can be very productive because of its power…much more so than Windows in many things. It takes a long time to get to that point though. Windows chews up a lot of horsepower 1) making things look good and 2) being helpful to the user and shielding them from the computer’s power to screw things up (preferring instead to screw things up itself). Item 1 appeals to business people for whom looking good is more important than actual results. Item 2 …I’m not sure who item 2 appeals to. It seems to get in most peoples way. I like the idea and the power of Linux…even if I’m not very productive with it right now.