#pragma	module	tcpip$tcp_server_sock_auxs		\
		"V5.4-00"

/*
 * © Copyright 1976, 2003 Hewlett-Packard Development Company, L.P.
 *
 * Confidential computer software.  Valid license  from  HP  and/or its
 * subsidiaries required for possession, use, or copying.
 *
 * Consistent with FAR 12.211 and 12.212, Commercial Computer Software,
 * Computer Software Documentation,  and  Technical Data for Commercial
 * Items  are  licensed to the U.S. Government under vendor's  standard
 * commercial license.
 *
 * Neither HP nor any of its subsidiaries shall be liable for technical
 * or editorial errors or omissions contained herein.   The information
 * in  this document is provided  "as is"  without warranty of any kind
 * and is subject  to  change  without  notice.   The warranties for HP
 * products are set forth in the express  limited  warranty  statements
 * accompanying such products.   Nothing herein should be construed  as
 * constituting an additional warranty.
 *
 * ++
 * FACILITY:
 *
 *    EXAMPLES
 *      
 * ABSTRACT:
 *
 *    This is an example of a TCP/IP IPv4 server using  4.x BSD
 *    socket Application Programming Interface (API) to  handle
 *    network I/O operations.  In addition,  it  shows  how  to
 *    accept connections from the auxiliary server.
 *
 *    Refer to 'Build, Configuration, and Run Instructions' for
 *    details on how to build, configure, and run this program.
 *
 * ENVIRONMENT:
 *
 *    OpenVMS Alpha/VAX V7.1
 *    TCP/IP Services V5.0 or higher
 *
 * AUTHOR:
 *
 *    TCPIP Development Group,  CREATION DATE: 23-May-1989
 *
 * --
 */

	/* Build, Configuration, and Run Instructions */

/*
 *  BUILD INSTRUCTIONS:
 *
 *    To build this example program use commands of the form,
 *
 *    using the "C" compiler:
 *
 *	$ cc/prefix=all TCPIP$TCP_SERVER_SOCK_AUXS.C
 *      $ link TCPIP$TCP_SERVER_SOCK_AUXS
 *
 *
 * CONFIGURATION INSTRUCTIONS:
 *
 *    To configure this example program:
 *
 *    1) Create a service run command procedure, named HELLO_RUN.COM, that
 *       contains the following lines:
 *
 *	 $ define sys$output ddcu:[directory]hello_service.log
 *	 $ define sys$error  ddcu:[directory]hello_service.log
 *	 $ run ddcu:[directory]tcpip$tcp_server_sock_auxs.exe
 *
 *	 where: ddcu:[directory] is the device and directory of where the
 *		hello service run command procedure file resides
 *
 *    2) Create a service database entry for the hello service as shown below:
 *
 *	 $ tcpip set service hello -
 *	 _$ /port=12345 -
 *	 _$ /protocol=tcp -
 *	 _$ /user=vms_user_account -
 *	 _$ /process_name=hello_world -
 *	 _$ /file=ddcu:[directory]hello_run.com
 *	
 *    3) Enable the hello service to run as shown below:
 *
 *	 $ tcpip enable service hello
 *
 *
 * RUN INSTRUCTIONS:
 *
 *    To run this example program:
 *
 *    1) Start the client program, entering the server host as shown below:
 *
 *	 $ run tcpip$tcp_client_sock
 *	 Enter remote host:
 *
 *	 Note: You can specify a server host by using either an IPv4
 *	       address in dotted-decimal notation (e.g. 16.20.10.56)
 *	       or a host domain name (e.g. serverhost.hp.com).
 *
 *    2) The auxiliary server receives the hello service request, creates a
 *       process, then executes the commands in hello_run.com to  run  this
 *       server program.  This server program then logs  client  connection
 *	 information and client data to the service log before replying  to
 *	 the client host with a message of "Hello, world!".
 *
 */


/*
 * INCLUDE FILES:
 */

#include <in.h>			    /* define internet related constants,   */
				    /* functions, and structures	    */
#include <inet.h>		    /* define network address info	    */

#include <socket.h>		    /* define BSD 4.x socket api	    */
#include <stdio.h>		    /* define standard i/o functions	    */
#include <stdlib.h>		    /* define standard library functions    */
#include <string.h>		    /* define string handling functions	    */

#include <tcpip$inetdef.h>	    /* define tcp/ip network constants,	    */
				    /* structures, and functions	    */

#include <unixio.h>		    /* define unix i/o			    */


/*
 * FORWARD REFERENCES:
 */

int  main( void );			/* server main			    */

	/* Server Main */

/*
 * FUNCTIONAL DESCRIPTION:
 *
 *    This is the server's main-line code. It handles all the tasks of the
 *    server including:  socket creation,  writing client connection data,
 *    and terminating client connections.
 *
 *    This example program implements a typical TCP IPv4 server using  the
 *    BSD socket  API  to  handle network i/o operations.  In addition, it
 *    uses the auxiliary server to accept client connections.
 *
 *	1) To create a socket:
 *
 *	   socket()
 *
 *	2) To transfer data:
 *
 *	   send()
 *
 *	3) To close a socket:
 *
 *	   close()
 *
 *    This function is invoked by the DCL "RUN" command (see below);  the
 *    function's  completion  status is interpreted by DCL and if needed,
 *    an error message is displayed.
 *
 * SYNOPSIS:
 *
 *    int main( void )
 *
 * FORMAL PARAMETERS:
 *
 *    ** None **
 *
 * IMPLICIT INPUTS:
 *
 *    ** None **
 *
 * IMPLICIT OUTPUTS:
 *
 *    ** None **
 *
 * FUNCTION VALUE:
 *
 *    completion status
 *
 * SIDE EFFECTS:
 *
 *    ** None **
 *
 */ 

int
main( void )
{
    int sockfd;				/* socket descriptor		    */

    unsigned int client_addrlen;	/* returned length of client socket */
					/* address structure		    */
    struct sockaddr_in client_addr;	/* client socket address structure  */

    char buf[] = "Hello, world!";	/* server data buffer		    */

    /*
     * init client's socket address structure
     */

    memset( &client_addr, 0, sizeof(client_addr) );

    /*
     * create socket
     */

    if ( (sockfd = socket(TCPIP$C_AUXS, SOCK_STREAM, 0)) < 0 )
	{
	perror( "Failed to create socket" );
	exit( EXIT_FAILURE );
	}

    /*
     * log this client connection
     */

    client_addrlen = sizeof(client_addr);

    if ( getpeername(sockfd,
		     (struct sockaddr *) &client_addr, &client_addrlen) < 0 )
	{
	perror( "Failed to accept client connection" );
	exit( EXIT_FAILURE );
	}

    printf( "Accepted connection from host: %s, port: %d\n",
	    inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port)
	  );

    /*
     * connection established with a client;
     * now attempt to write on this connection
     */

    if ( send(sockfd, buf, sizeof(buf), 0) < 0 )
	{
	perror( "Failed to write data to client connection" );
	exit( EXIT_FAILURE );
	}

    printf( "Data sent: %s\n", buf );	   /* output server's data buffer  */

    /*
     * close socket
     */

    if ( close(sockfd) < 0 )
	{
	perror( "Failed to close socket" );
	exit( EXIT_FAILURE );
	}

    exit( EXIT_SUCCESS );
}