View difference between Paste ID: 7ptZkYHa and jQabZSkJ

 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/wait.h>
 #include <string.h>
 
 int main(void)
 {
     int pid,
         c_fd[2],
         p_fd[2];
 
     char *str;
 
     if (pipe(c_fd) == -1 || pipe(p_fd) == -1)
     {
         fprintf(stderr, "Pipe failed.\n");
         exit(1);
     }
 
     pid = fork();
     if (pid == -1)
     {
         fprintf(stderr, "Fork failed.\n");
         exit(1);
     }
     // child process
     else if (pid == 0)
     {
         // redirect stdin to c_fd output and close c_fd input
         dup2(0, c_fd[0]);
         close(c_fd[1]);
 
         // redirect stdout to p_fd input and close p_fd output
-        printf("Oh, hallo!\n");
+
         close(p_fd[0]);
 
         while (read(c_fd[0], &str, 11) != 0)
             if (strcmp(str, "Guten Tag!\n") == 0)
                 printf("Oh, hallo!\n");
 
         exit(0);
     }
     // parent process
     else
     {
         // redirect stdout to c_fd input and close c_fd output
         dup2(1, c_fd[1]);
         close(c_fd[0]);
 
         // redirect stdin to p_fd output and close p_fd input
         dup2(0, p_fd[0]);
         close(p_fd[1]);
 
         printf("Guten Tag!\n");
 
         wait(&pid);
 
         printf("Kindprozess hat erfolgreich geantwortet!\n");
     }
 
     return 0;
 }