DouKaku?

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

#define R (0)
#define W (1)

int main( void ){
   char buf[1024];
   int status = 0;
   int pipe_c2p[2];
   ssize_t read_size;
   pid_t pid;
   char command[] = "date";

   if( pipe(pipe_c2p) == -1 ){
      perror("pipe");
      exit(1);
   }

   pid = fork();

   if( pid < 0 ){ /* fail to fork */
      close( pipe_c2p[W] );
      close( pipe_c2p[R] );
      perror("fork");
      exit(1);
   }
   else if( pid == 0 ){ /* child process */
      close( pipe_c2p[R] );
      dup2( pipe_c2p[W], 1 );
      close( pipe_c2p[W] );
      execlp("/bin/sh", "sh", "-c", command, NULL);
   }
   else{ /* parent process */
      close( pipe_c2p[W] );
      while( (read_size = read( pipe_c2p[R], buf, sizeof(buf)-1 ) ) > 0 ){
         buf[read_size] = '\0';
         printf("%s",buf);
      }
      if( read_size == -1 ){
         perror("read");
      }
      close( pipe_c2p[R] );
      if( waitpid( pid, &status, 0 ) == -1 ){
         perror("waitpid");
         exit(1);
      }
      if( WIFEXITED(status) ){
         printf("child process exit with status %d\n", WEXITSTATUS(status) );
      }
   }

   return 0;
}