libudev advice needed

Question

I am embarking on a programming project that will need to confirm device identity of removable media (eg usb thumb drives) before it will go on to do a bunch of other cool stuff.

Some friends of mine pointed me towards using the Serial Number, and preliminary testing using the udevadm command indicates that this should work. I did some additional checking and it appears that if I can get the software working with libudev then it should (minimally) compile on ubuntu, slackware and gentoo, which would be a really nice benefit.

So I used bing to find a tutorial and got the Signal 11 site (http://www.signal11.us/oss/udev/) it's a very well-written tutorial. It actually seems to have everything I need. I download the code. Fix a couple of platform-specific bugs and then compile. BOOM! Gcc compiles without errors. So far so good.

But when I try to run it, it kicks up a couple of bugs, and I realize that I need to read some more tutorials so that I can understand libudev well enough to fix the bugs, and to turn out working software. Problem is that there really ISN'T any other tutorials (that I can find) and the kernel.org site that is the (only known?) site of the library documentation is down after a recent server compromise.

I considered just issuing udevadm directives to system() and then parsing results, but that's a really hackish way to put software together, and I am planning on releasing this to the community when I'm finished writing.

So how best for me to learn libudev??

Answer 1

libudev is quite simple library. After reading library you've mentioned and using API documentation (site should be soon up) I was able to get what I wanted. udevadm is great help, after issuing # udevadm info --query=all --name=/path/to/dev you'll get all information that udev has about this device and what's more important, these are parameters used in property functions (eg udev_device_get_property_value(device, "ID_VENDOR") ). So best way to learn libudev is to start using it with help of signal11 tutorial, API documentation and udevadm informations.

EDIT: libudev is currently part of systemd - documentation is available as manual pages - https://www.freedesktop.org/software/systemd/man/libudev.html#