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Re: Dereferencing simple pointers


daniel-kay3@arcor.de writes:

> I am playing around with systemtap and am quite impressed. But there
> is one thing that confuses me. Is there any way that I can
> derefernce a single pointer from a function parameter inside a
> probe?

> [...]
> # My Probe Attempt without success:
> probe kernel.function("urandom_read") {
>         printf("%s\n", *($ppos));
> }
>
> I can't believe that this isn't possible...

Right, we don't currently use "*" as a derferencing operator, but
instead make a family of functions available:
kernel_{char,...,long,string} and user_{char,...,long,string}:
So if $ppos was a just a random old char* string,

         printf("%s\n", kernel_string($ppos))

- FChE


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