/************************************************************************
*                                                                       *    
*  Copyright Digital Equipment Corporation 1998. All rights reserved.   *
*                                                                       *    
*  Restricted Rights: Use, duplication, or disclosure by the U.S.       *    
*  Government is subject to restrictions as set forth in subparagraph   *    
*  (c) (1) (ii) of DFARS 252.227-7013, or in FAR 52.227-19, or in FAR   *    
*  52.227-14 Alt. III, as applicable.                                   *    
*                                                                       *    
*  This software is proprietary to and embodies the confidential        *    
*  technology of Digital Equipment Corporation. Possession, use, or     *    
*  copying of this software and media is authorized only pursuant to a  *    
*  valid written license from Digital or an authorized sublicensor.     *    
*                                                                       *    
************************************************************************/

/*      decc$set_child_standard_streams_example.c       */

/* Demonstrate the use of decc$set_child_standard_streams       */
/* with both an executable child and a command file child       */

#include <stdio.h>
#include <string.h>
#include <unistd.h>
 
int decc$set_child_standard_streams(int, int, int);

const char *exe_child = "decc$set_child_standard_streams_child.exe" ;
const char *com_child = "decc$set_child_standard_streams_child.com" ;

char msg[] = "parent writing to child's stdin";


void call_child(const char *child_name)
{
    char buf[80];
    int nbytes;
    int fdin[2], fdout[2], fderr[2];

    pipe(fdin);
    pipe(fdout);
    pipe(fderr);

    printf("Parent is calling %s\n", child_name) ;

    if ( vfork() == 0 ) {
        decc$set_child_standard_streams(fdin[0], fdout[1], fderr[1]);
        execl( child_name, "child" );
    }
    else {
        write(fdin[1], msg, sizeof(msg));
        nbytes = read(fdout[0], buf, sizeof(buf));
        buf[nbytes] = '\0';
        puts(buf);
        nbytes = read(fderr[0], buf, sizeof(buf));
        buf[nbytes] = '\0';
        puts(buf);
    }
}
main()
{
    call_child(exe_child) ;     /* Call teh executable child     */

    call_child(com_child) ;     /* and the same for the com file */

}