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Old 09-14-2010, 05:49 AM   #1
mandeep.singh.bhatia
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about linux sendto


Hi,
I just need to get this clarified. When we send character data buffer with sento over udp socket, does sendto make a copy of the buffer or does it just take the pointer and size and send the data buffer from pointed location.
I ask this for understanding that would it be legal or illegal to allocate a memory buffer then call sendto in non-block mode and then immediately delete the allocated memory, or, a case where we keep a common buffer and in a loop change the value of buffer and call sendto.
Regards,
Mandeep
 
Old 09-14-2010, 08:14 AM   #2
dugan
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If it sent a pointer, then how would the remote machine be able to access the data? The remote machine can't read memory on the local machine.

I haven't actually checked this, but I think it must send a copy of the buffer.

Last edited by dugan; 09-14-2010 at 08:19 AM.
 
Old 09-14-2010, 11:45 PM   #3
mandeep.singh.bhatia
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Quote:
Originally Posted by dugan View Post
If it sent a pointer, then how would the remote machine be able to access the data? The remote machine can't read memory on the local machine.

I haven't actually checked this, but I think it must send a copy of the buffer.
Hi, actually I meant that the sendto might just read from the buffer location via the pointer passed and send out data directly from the pointed buffer instead of making its own copy. I wanted to be sure of what is happening and how it happens.
Regards,
Mandeep
 
  


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