/* I want to write programs for OS/2 in C. I want to use OpenWatcom v2
 * as a compiler and I want to compile the code on Linux.
 *
 * By default, OpenWatcom v2 links against TCPIP32.DLL, which is not
 * present in default installations of OS/2 Warp 3 or 4. Those only come
 * with SO32DLL.DLL and TCP32DLL.DLL, i.e. an older 16 Bit TCP/IP stack.
 * I do want to use that older stack, though, because I want to stay
 * close to the "original" Warp 3 and 4 versions and want to avoid
 * having to install all kinds of additional stuff.
 *
 * OpenWatcom does not include the headers nor LIB files for that older
 * stack.
 *
 * As a workaround, I used files from the OS/2 Toolkit 4.5.
 *
 * Step 1: Acquire IBM OS/2 DEVELOPER'S TOOLKIT VERSION 4.5.2.
 * Step 2: Replace backslashes with slashes in include directives, e.g. 
 *         replace
 *             #include <netinet\in.h>
 *         with:
 *             #include <netinet/in.h>
 *         This applies to all files in the directory "h/stack16" in the
 *         TK.
 *
 * Then compile as follows:
 *
 *     export INCLUDE=/path/to/os2tk45/h/stack16:/opt/watcom/h:/opt/watcom/h/os2
 *     owcc -Wall -Wextra -std=c99 -bos2v2 \
 *         -o test.exe connect-tk45-stack16.c \
 *         /path/to/os2tk45/lib/so32dll.lib /path/to/os2tk45/lib/tcp32dll.lib
 *
 * This places the TK headers before OpenWatcom's own headers and uses
 * the TK LIB files for linking.
 *
 * The resulting EXE file works on Warp 3 and 4, but this whole process
 * feels quite wonky. */

/* OpenWatcom headers */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

/* OS/2 TK 4.5 headers */
/* sockaddr, sockaddr_in, socket(), AF_INET, SOCK_STREAM, htons(),
 * select(), send(), recv() */
#include <sys/socket.h>
/* gethostbyname() */
#include <netdb.h>

int
main(int argc, char **argv)
{
    int s, ret;
    struct sockaddr_in sa = {0};
    char buf[4096], *msg;
    struct hostent *he;

    if (argc < 3)
    {
        fprintf(stderr, "Usage: %s <host> <port>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    he = gethostbyname(argv[1]);
    if (he == NULL)
    {
        perror("gethostbyname()");
        exit(EXIT_FAILURE);
    }

    s = socket(AF_INET, SOCK_STREAM, 0);
    if (s == -1)
    {
        perror("socket()");
        exit(EXIT_FAILURE);
    }

    sa.sin_family = AF_INET;
    sa.sin_addr.s_addr = *((unsigned long *)he->h_addr);
    sa.sin_port = htons(atoi(argv[2]));

    if (connect(s, (struct sockaddr *)&sa, sizeof sa) == -1)
    {
        perror("connect()");
        exit(EXIT_FAILURE);
    }

    msg = "GET / HTTP/1.0\r\n";
    send(s, msg, strlen(msg), 0);

    msg = "Host: ";
    send(s, msg, strlen(msg), 0);

    send(s, argv[1], strlen(argv[1]), 0);

    msg = "\r\n\r\n";
    send(s, msg, strlen(msg), 0);

    while ((ret = recv(s, buf, sizeof buf, 0)) > 0)
        write(STDOUT_FILENO, buf, ret);

    soclose(s);

    exit(EXIT_SUCCESS);
}