Agilent Technologies E4428C - Page 122

112 Agilent N518xA, E8663B, E44x8C, and E82x7D Signal Generators Programming Guide
Programming Examples
LAN Programming Interface Examples
*
* $Return: (int) . . . . . . . . A file descriptor similar to open(1).$
*
* $Errors: returns -1 if anything goes wrong $
*
***************************************************************************/
SOCKET openSocket(const char *hostname, int portNumber)
{
struct hostent *hostPtr;
struct sockaddr_in peeraddr_in;
SOCKET s;
memset(&peeraddr_in, 0, sizeof(struct sockaddr_in));
/***********************************************/
/* map the desired host name to internal form. */
/***********************************************/
hostPtr = gethostbyname(hostname);
if (hostPtr == NULL)
{
fprintf(stderr,"unable to resolve hostname '%s'\n", hostname);
return INVALID_SOCKET;
}
/*******************/
/* create a socket */
/*******************/
s = socket(AF_INET, SOCK_STREAM, 0);
if (s == INVALID_SOCKET)
{
fprintf(stderr,"unable to create socket to '%s': %s\n",
hostname, strerror(errno));
return INVALID_SOCKET;
}
memcpy(&peeraddr_in.sin_addr.s_addr, hostPtr->h_addr, hostPtr->h_length);
peeraddr_in.sin_family = AF_INET;
peeraddr_in.sin_port = htons((unsigned short)portNumber);
if (connect(s, (const struct sockaddr*)&peeraddr_in,
sizeof(struct sockaddr_in)) == SOCKET_ERROR)