Re: memory address represented as a string

[Saurabh Sehgal <saurabh.r.s@gmail.com>]

Hi all,

Thanks for the reply !

I was able to write this function successfully.

This would lead me to my next question.

Is there anyway to test if a memory address is valid or not without causing a
segmentation fault and catching this maybe in a signal handler ?

Is there a safe way in the same function " void * foo (char * addr)"
to check that
if the address contained in the string represented by "char * addr"  is valid
before returning it.

Thank you !

Saurabh

On Sun, Jul 26, 2009 at 4:14 AM, Eric Polino<aluink@gmail.com> wrote:
> sure, you can just write a function that declares a void * and uses it as a
> regular numeric type such as int or whatnot and parses the string
> representation as a numeric value into that variable.  You can do stuff the
> same as you would with any other integer type, "x += 10; x -= 18;".  So the
> function would look something like
>
> void *foo(const char *addr){
>   void *parsed_value = 0;
>   ....
>   /* Parse addr into parsed_value */
>   ....
>   /* parsed_value == value_described_by(addr) */
>
>   return parsed_value;
> }
>
> Parsing addr into parsed_value is left as an exercise to the reader ;)
>
> "None are more hopelessly enslaved than those who falsely believe they are
> free."
>                                      --Goethe
>
> "Freedom is living without government coercion."
>                   --Ron Paul (www.ronpaul2008.com)
>
>
> On Sun, Jul 26, 2009 at 03:39, Saurabh Sehgal <saurabh.r.s@gmail.com> wrote:
>>
>> Hi all,
>>
>> I had a quick question:
>>
>> Let's say I design a function with the signature:
>>
>> void * foo( char * addr ) ; ,
>>
>> where addr is a string that represents a valid memory address  ...
>> so the way someone can call this function is ...
>>
>> char * addr = "0xae456778" // assume this is a valid memory address on
>> the machine
>> foo( addr ) ;
>>
>> Is it possible to take this address in string form, and assign it to
>> an actual pointer of void * type ?
>> I want the function "foo" to return a pointer pointing to the memory
>> location as indicated
>> by the string passed in.
>>
>> Thank you !
>>
>> Saurabh
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>
>



-- 
Saurabh Sehgal
E-mail:     saurabh.r.s@gmail.com
Phone:     647-831-5621
LinkedIn: http://www.linkedin.com/pub/1/7a3/436
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