Probable reasons for Illegal seek in socket programming [closed] - c++

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I have received following error while sending data.
send:29-Illegal seek
Please explain the probable reasons for it. I am new to socket programming. Thanks in advance.
CHAR datasend[200];
DOUBLE64 fTime=0.0;
LONG32 sent_bytes=0;
while(TRUE)
{
memset(datasend,0,200);
fTime=getTime();
sprintf(datasend,"0=%.0lf ",fTime);
sent_bytes = send ( isockfd, datasend, strlen(datasend),0);
logDebug1("Pulse is %s and data bytes is %d",datasend,strlen(datasend));
if(sent_bytes <= 0)
{
logPError("send");
logTimestamp("Closing socket\n");
close(isockfd);
return NULL;
}
sleep(25);
}

Answer 1

You're not interpreting the right error because of the intervening logDebug1 call.
You have a send that returns something <= 0 and possibly an errno that you could inspect
You print something (logDebug1) which likely clobbers errno
You do some sort of perror which interprets the clobbered errno
What you want to do instead is check if sentBytes < 0, perror immediately and then maybe print more debugging stuff if you want.