Re: fprintf() and duplicate IP addresses

["M.Baris Demiray" <baris@labristeknoloji.com>]

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Hello again,
Thanks for the comments Mikael and Jarmo. As you said, the problem was
caused by the usage of static buffers in inet_ntoa() and fprintf() was
innocent at all. Since only the char * values are saved in fprintf(),
every inet_ntoa() overwrites the previous' values.

This was also written in man page (argh!):
"The string is returned in a statically allocated buffer, which
  subsequent  calls  will  overwrite."

I think I didn't searched enough to see that this is a common problem.

Everything is more clear now, thanks.

mikael-aronsson wrote:
> That's correct, most implementations use a static buffer, even though 
> most modern applications has a separate buffer for each thread.
> 
> Mikael

 > [...]

>> I have nothing to back my suspection with. But probably inet_ntoa(...) 
>> uses an internal buffer.
>>
>> printf( ) solves variables from the right, _before_ adding the result 
>> to the output (only the "pointer" to char* is saved), you only get the 
>> result from the first one (as they "point" to same memory).
>>
>> // Jarmo

-- 
"You have to understand, most of these people are not ready to be
unplugged. And many of them are no inert, so hopelessly dependent
on the system, that they will fight to protect it."
                                                         Morpheus

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