send() trashing data

I am reading a file and writing the contents to a port using send(). The data is corrupted - missing data on the start and extra junk on the end. Here is my code, could someone tell me what I am doing wrong?

char buffer[16384];
long i, iRead;

send(socket, “This works!”, 10, 0);

for(i = 0; i < size; i += iRead)
iRead = fread(buffer, 1, sizeof(buffer)-16, fp);
if( iRead <= 0 ) break;
//buffer[iRead] = ‘\0’;
//printf(“%s”, buffer); // Test to see if data correct
send(socket, (const char *)buffer, iRead, 0);

P.S. The fread() is returning the correct data. Also this is NetOS7.4.


You did not say what platform you doing your development work on, but there is an excellent “Serial Driver Sample” application available under the Connect Core 9P-9360 platform.

I would recommend looking at this for some guidance. This sample application demonstrates sending data from one serial port (TEST_COM0) to another serial port(TEST_COM1) of the NET+OS development board. The data is then stored in a file (data.c).

Let me know if this example doesn’t answer your questions.


Digi updated the forums to stop spammers from posting.

>>send(socket, “This works!”, 10, 0);
you’re only sending 10 bytes out of the 11 in the string, so you’re losing a byte you think you should have.

Try throwing ‘static’ in front of char buffer[16384], i.e.:

static char buffer[16384];

It could be your buffer is too large and is getting corrupted because of a stack overflow.

Other than those two things, I don’t see anything wrong with the snippet you sent. If the above doesn’t fix it, I’d have to see the actual code (or a simplified example that reproduces the problem).

Thanks for your reply.
I posted to the ConnectME forum, I am using a ConnectME 9210. Serial ports aren’t an issue, I am working with a Ethernet port that is messing up.


P.S. The tag used to work a long time ago. Digi must have “updated” the forum software and broken it.

Thanks for the reply.

I finally solved it - a rookie mistake. In a string before the code snippit I was sending a string, but stupidly put a sizeof() for the length. All the extra NULLs messed up the web browsers (both IE and mozilla). Switched to a strlen() and everything works.