Agilent Technologies E4406A VSA manual Programming Examples, Using C Programming Over Socket LAN

	Programming Examples
	Using C Programming Over Socket LAN
*	Use 5025 for the SCPI port.
*
* $Return:	(int) . . . . . . . . A file descriptor similar to open(1).$
*
* $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;

}

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