How to use the C socket API in C++ on z/OS

Keep a copy of the IBM manuals handy:

• z/OS V1R11.0 XL C/C++ Programming Guide
• z/OS V1R11.0 XL C/C++ Run-Time Library Reference

The IBM publications are generally very good, but you need to get used to their format, as well as knowing where to look for an answer. You'll find quite often that a feature that you want to use is guarded by a "feature test macro"

You should ask your friendly system programmer to install the XL C/C++ Run-Time Library Reference: Man Pages on your system. Then you can do things like "man connect" to pull up the man page for the socket connect() API. When I do that, this is what I see:

FORMAT

X/Open

#define _XOPEN_SOURCE_EXTENDED 1
#include <sys/socket.h>

int connect(int socket, const struct sockaddr *address, socklen_t address_len);

Berkeley Sockets

#define _OE_SOCKETS
#include <sys/types.h>
#include <sys/socket.h>

int connect(int socket, struct sockaddr *address, int address_len);

I've had no trouble using the BSD sockets API in C++, in GNU/Linux. Here's the sample program I used:

#include <sys/socket.h>

int
main()
{
    return AF_INET;
}

So my take on this is that z/OS is probably the complicating factor here, however, because I've never used z/OS before, much less programmed in it, I can't say this definitively. :-P