/*-------------------------------------------------------------------*/
/* testpipedup.c                                                     */
/* The pipe and dup system calls.                                    */
/*-------------------------------------------------------------------*/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define BUFFER_SIZE 100

int main(int argc, char *argv[])
{
   int piPipeFd[2];
   int iProducerPid;
   int iConsumerPid;
   int iRet;

   iRet = pipe(piPipeFd);
   if (iRet == -1) {perror(argv[0]); return 1; }

   fflush(NULL);
   iProducerPid = fork();  /* Fork a producer child. */
   if (iProducerPid == -1) {perror(argv[0]); return 1; }

   if (iProducerPid == 0)
   {
      /* Producer child */

      iRet = close(piPipeFd[0]);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = close(1);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = dup(piPipeFd[1]);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = close(piPipeFd[1]);
      if (iRet == -1) {perror(argv[0]); exit(1); }

      printf("somedata\n");
      exit(0);
   }

   fflush(NULL);
   iConsumerPid = fork();  /* Fork a consumer child. */
   if (iConsumerPid == -1) {perror(argv[0]); return 1; }

   if (iConsumerPid == 0)
   {
      /* Consumer child */

      char pcBuffer[BUFFER_SIZE];

      iRet = close(piPipeFd[1]);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = close(0);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = dup(piPipeFd[0]);
      if (iRet == -1) {perror(argv[0]); exit(1); }
      iRet = close(piPipeFd[0]);
      if (iRet == -1) {perror(argv[0]); exit(1); }

      scanf("%s", pcBuffer);

      /* Print the data to make sure it was communicated properly. */
      printf("%s\n", pcBuffer);
      exit(0);
   }

   iRet = close(piPipeFd[0]);
   if (iRet == -1) {perror(argv[0]); return 1; }
   iRet = close(piPipeFd[1]);
   if (iRet == -1) {perror(argv[0]); return 1; }

   return 0;
}

/* Sample execution:

--> testpipe
somedata
-->

*/