detect usb device insert/remove and get device node from "C" program
 

Hello Everybody,

My application (running on an embedded MIPS based platform, running linux and has 2 USB ports) needs to detect USB devices such as Mass Storage devices that has been inserted/removed. The application need to know that a usb device has been inserted/removed along with the device node (like /dev/sda1, /dev/sdb1 etc). Then I need to mount this device node to a known location in the application.

Is there a way to get these 2 things, from my application, which is in C language.

1) usb device inserted/removed (Is there a way like an interrupt or polling).
2) device node

Thanks in advance,
Ebin.

With kernels that have 'udev', you can abuse udev to alert your program of any USB related event (for example, send -SIGUSR1 for a connect event and -SIGUSR2 for a disconnect). You can then go through the sysfs virtual filesystem and get the information you need.

If you use the 'RUN+=' feature of udev, whatever program you invoke will have access to a *lot* of information about the device being connected/disconnected via environment variables; the program invoked can then send the relevant information to your other software via a pipe or some such - personally I prefer a UNIX socket - or even a TCP socket communicating on 127.0.0.1.

The udev documentation has improved significantly, but there are still numerous features which are undocumented; if you want to do anything serious with udev, there is a good chance you'll have to find the time to read the source. (And while at it, I'm sure that people would appreciate patches to the documentation.)

Any practical solution to this problem?

closed
 

Done with udev. Can be closed. Thanks guyz.

Can you please explain how you did it with udev?