Dear Sirs,

Would you mind to tel me what is function or the way to determine that the data is sent by the socket send function in C language?

Besides, please suggest where can I search for all the C language APIs reference in Linux?

Thank you very much.

Alan.

I would recommend "man send" and look at the section titled "RETURN VALUE".

Once again, the man pages are the easiest to use reference for these questions. You can even access the man pages on the web.

Hi David,

Many thanks on your reply.

I checked the the return value of the send function. It just gave how many byte of data is successful sent. However, the data is not really sent out from the system on this API reply. It just pass the data to lower layer and waiting for send physically. For my question, I want to know whether Linux has API for me to check whether there are data waiting for send in network layer. Sorry to tell that, my application is send data through by socket connection.

For the man page on web, it is really very useful. thank you very much.
By the way, is there any others which will group the APIs by features, eg. network connection and etc.

Thank you again.

Alan.

I think we need to see your code. Your qn is not that clear (to me anyway).

I was looking through /usr/include/linux/sockios.h for an ioctl that might help, but I didn't see one. Generally receipt is more important than transmission; therefore, you might consider having the receiver send a response and wait for it at the sender before moving on.
ta0kira

Hi,

Thank you for all of your replies.
Let me talks about more about my application.
Actually, the Linux system is running in an embedded system and it will send data through socket connection only. The system will fall in suspend mode regularly. So when the system woke up and let the application to send data out. After the data is sent in application layer, i.e it has reply from send api already, the system fall in suspend again. Then I found there is data lost due to system slept.

So my question is how I know that the data is really sent out before the system sleep.

Thanks again to all of you.

Alan.

Like ta0kira said, have the receiver send a confirmation back.