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problems with opening my device driver

problems with opening my device driver

problems with opening my device driver

(OP)
Hi!
I just started writing device drivers for Linux...
After compiling and loading my driver with out any problems I run into trouble while trying to open it.
Here is how I open my driver in user space:
int fd = open("\dev\my_driver", O_RDWR);
the value of the returned is '3' (always '3' strange enough), ok so far. But when I look at the traceouts from my driver I see that the 'struct file *filp' also has the value of '3', why is that? I excpected a pointer value to a file struct and not the fd value.
Any body how can help me?
Does any one have a very short code sequence on how to load a device driver?
thanks in advance
/Lars

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