#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>

#define BUFF_SIZE 255

int main(int ac, char* av[])
{
    if(ac <3)
    {
        printf("Please enter all required arguments!n");
        exit(0);
    }

    int pfd[2];
    int pipeCreated;

    char readFile[50];
    char writePipe[20];

    pid_t child_pid_read;
    pid_t child_pid_write;

    pipeCreated = pipe(pfd);

    if(pipeCreated == -1)
    {
        printf("An error occurred when trying to create a pipen");
        exit(0);
    }

    strcpy(readFile, av[1]);
    sprintf(writePipe,"%d", pfd[1]);

    child_pid_read = fork();

    char writeFile[50];
    char readPipe[20];

    //Handling the read()
    switch(child_pid_read)
    {
        //Error in case forfk() failed
        case -1:
            perror("fork failed");
            return 1;

            //Handle child processes
        case 0:
             if(close(pfd[0]) == -1)
             {
                 printf("An error occurred while closing the pipen");
                 exit(0);
             }
             if(execle("./read.out", "./read.out", readFile, writePipe, (char*)0, NULL) == -1)
             {
                 printf("Child: Error creating read.n");
                 exit(0);
             }

        default:
            wait(&child_pid_read);

            strcpy(writeFile, av[2]);
            sprintf(readPipe,"%d", pfd[0]);

            child_pid_write = fork();
            break;
    }

    //Handling the write
    switch(child_pid_write)
    {
        //Error in case fork() failed
        case -1:
            perror("fork failed");
            return 1;

        //Handle child processes
        case 0:
            if(close(pfd[1]) == -1)
            {
                printf("An error occurred while closing the pipen");
                exit(0);
            }

            if(execle("./write.out", "./write.out", writeFile, readPipe, (char*)0, NULL) == -1)
            {
                printf("Child: Error creating read.n");
                exit(-1);
            }
            break;

        default:
            wait(&child_pid_write);
            break;
    }
    printf("Write completed!");
    return 0;
}

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

#define BUFF_SIZE 16

int main(int ac, char* av[])
{
    char buffer[BUFF_SIZE];
    int fd;
    int pid;

    if(ac > 1)
    {
        fd = open(av[1], O_RDONLY);
        if(fd == -1)
        {
            printf("error: Could Not Open Filen");
            exit(0);
        }

        pid = atoi(av[2]);

    }

    int num_read = 1;

    while(1)
    {
        num_read = read(fd, buffer, BUFF_SIZE);

        if(num_read == -1)
        {
            printf("Error reading filen");
            exit(0);
        }

        if(num_read == 0)
        {
            break;
        }

        if(write(pid, buffer, num_read) != num_read)
        {
            printf("Error writing to pipen");
            break;
        }
    }
    close(fd);
    return 1;
}

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

#define BUFF_SIZE 1

int main(int ac, char* av[])
{
    char buffer[BUFF_SIZE];

        int fd = open(av[1], O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);

        int pid = atoi(av[2]);

        int num_read = 1;

    while(1)
    {
            num_read = read(pid, buffer, BUFF_SIZE);

            printf("num_read: %dn", num_read);

            if(num_read == -1)
            {
                printf("Error reading pipen");
                break;
            }

            if(write(fd, buffer, num_read) != num_read)
            {
                printf("Error writing to filen");
                break;
            }

            if(num_read == EOF)
            {
                break;
            }
    }

        close(fd);
        return 1;
}

default:
    if(close(pfd[0]) == -1)
     {
         printf("An error occurred while closing the pipen");
         exit(0);
     }
    wait(&child_pid_write);
    break;