Agilent Technologies E4406A VSA manual Using C Programming Over Socket LAN Windows NT, Synopsis

Programming Examples

Using C Programming Over Socket LAN (Windows NT)

Using C Programming Over Socket LAN (Windows NT)

This is the C programming example getopt.c that demonstrates simple socket programming. It is written in C, and compiles in the Windows NT environment.

In Windows, the routines send() and recv() must be used, since fread() and fwrite() may not work on sockets.

The program reads the analyzer’s host name from the command line, followed by the SCPI command. It then opens a socket to the analyzer, using port 5025, and sends the command. If the command appears to be a query, the program queries the analyzer for a response, and prints the response.

This example program can also be used as a utility to talk to your analyzer from the command prompt on your Windows NT PC, or from within a script.

/***************************************************************************

getopt(3C) getopt(3C)

NAME

getopt - get option letter from argument vector

SYNOPSIS

int getopt(int argc, char * const argv[], const char *optstring);

extern char *optarg;

extern int optind, opterr, optopt;

DESCRIPTION

getopt returns the next option letter in argv (starting from argv[1]) that matches a letter in optstring. optstring is a string of recognized option letters; if a letter is followed by a colon, the option is expected to have an argument that may or may not be separated from it by white space. optarg is set to point to the start of the option argument on return from getopt.

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