[SOLVED] bytes problem c++

vbx_wx · 02-03-2011, 07:15 AM

Hi,i am receing a packet through sockets that contains this bytes:

Code:

510175126-94-51080

The first 4 bytes should be ignored(5101) and the last 3(080,witch is the port) how can i extract the ip part from that(75126-94-51) ? Just to mention the ip it supossed to be 75.126.162.205. Thanks in advanced.

dwhitney67 · 02-03-2011, 09:37 AM

Use the STL string, and it's substr() function.

I know this looks a wee bit amateurish, but consider the following:

Code:

#include <string>
#include <iostream>

int main()
{
   const std::string data = "510175126-94-51080";
   const std::string ip   = data.substr(4, data.size() - 3 - 4);

   std::cout << "ip = " << ip << std::endl;
}

ForzaItalia2006 · 02-03-2011, 09:46 AM

Quote:

Originally Posted by vbx_wx

Hi,i am receing a packet through sockets that contains this bytes:

Code:

510175126-94-51080

The first 4 bytes should be ignored(5101) and the last 3(080,witch is the port) how can i extract the ip part from that(75126-94-51) ? Just to mention the ip it supossed to be 75.126.162.205. Thanks in advanced.

Hey,

may I ask why an IP address is encoded this way? When I would have to send an IP-adress across the network, I would not send it in ASCII, but in binary format, though 4 bytes per IP-address and 2 bytes per port. This is then much easier to parse/reconstruct and reduces the network load :-)

Andi

gothrog · 02-03-2011, 04:03 PM

Andi - I'd guess old school proprietary legacy format.

dwhiteney67 - But if you can, definitely change it to Andi's suggestion.