==== pipe.h ====

#include <fcntl.h>
#include <limits.h>
#define MAXLINE 40
#define LINES 11


==== mainpipe.c ====

#include "pipe.h"

void client(int, int), server(int, int);

int main ()
{
    int pipe1[2], pipe2[2];
    pid_t childpid;

    pipe(pipe1);
    pipe(pipe2);

    if((childpid = fork()) != 0) {
        close(pipe1[1]);
        close(pipe2[0]);

        server(pipe1[0], pipe2[1]);
        exit(EXIT_SUCCESS);
    }
    close(pipe1[0]);
    close(pipe2[1]);

    client(pipe2[0], pipe1[1]);

    waitpid(childpid, NULL, 0);
    exit(EXIT_SUCCESS);
} 

==== client.c ====

#include "pipe.h"

void print_array(char *d[], int);

void client(int readfd, int writefd)
{
    int i=0,j;
    size_t len;
    ssize_t n;
    char buff[MAXLINE];
    char word[LINES][MAXLINE];
    FILE *infile;
    FILE *outfile;

    printf("input a file name : ");

/*    fgets(buff, MAXLINE, stdin);*/
/*    len = strlen(buff);*/
/*    if (buff[len - 1] =='\n')*/
/*        len--;*/

/*    infile = fopen("unsorted", "r");*/
    infile = freopen("unsorted", "r",stdin);
    outfile = fopen("sorted", "w");
    
    while(fgets(word[i], MAXLINE, infile) != (char*) NULL) {
        word[i][strlen(word[i])-1] = '\0';
        i++;
    }
    printf("Before Sorted ... in client-side \n");

    for(i = 0;i < LINES;i++){
        printf("%d", len);
        for( j = 0; j <= 10; j++)
            buff[j] = word[i][j];
        len = strlen(word[i]);
        buff[len] = '\n';
        write(writefd, buff, len+1);
    }
    printf("\nAfter Sorted ... in client-side \n");

    for (i =0; i < LINES ; i++){
        n = read(readfd, buff, MAXLINE);
/*        write(STDOUT_FILENO, buff, n);*/
        fwrite(buff,n,1,outfile);
/*        len = strlen(buff);*/
/*        for( j = 0; j <= len; j++)*/
            word[i][j]= buff[j];
    }
}

void print_array(char *d[], int n)
{   
    int i;
    for(i=0;i<n;i++) 
        puts(d[i]);
}
==== server.c ====

#include "pipe.h"

void err_quit(char *msg);

void server(int readfd, int writefd)
{
    int fd;
    ssize_t n;
    char buff[MAXLINE + 1];
    char data[LINES][MAXLINE], *ptr[LINES];
    int i = 0, j;
    size_t len ;

    for (i =0; i < LINES ; i++){
        n = read(readfd, buff, MAXLINE);
        write(STDOUT_FILENO, buff, n);
        len = strlen(buff);
        for( j = 0; j <= len; j++)
            data[i][j]= buff[j];
/*        ptr[i] = data[i];*/
    }

    bubble_sort(data, LINES);

/*    for (i =0; i < LINES ; i++){*/
/*        data[i] = ptr[i];*/
/*        printf("ptr() %s", ptr[i]);*/
/*    }*/

    for(i = 0;i < LINES;i++){
/*        printf("%d", len);*/
        for( j = 0; j <= 10; j++)
            buff[j] = data[i][j];
        len = strlen(data[i]);
        buff[len] = '\n';
        write(writefd, buff, len);
    }
}

void err_quit( char *msg)
{
    perror(msg);
    exit(EXIT_FAILURE);
}
==== bubble.c ====
#include "pipe.h"

void bubble_sort(char data[][MAXLINE], int lim)
{
    int i, eff_size, maxpos =0;
    char tmp[MAXLINE];

    for (eff_size = lim ; eff_size > 1; eff_size--) {
        for ( i = 0 ; i < eff_size ; i++)
            if (strcmp(data[i], data[maxpos]) > 0)
                maxpos = i;

        strcpy(tmp, data[maxpos]);
        strcpy(data[maxpos], data[eff_size-1]);
        strcpy(data[eff_size-1], tmp);
    }
}