C/C++에서 압축 파일을 다루는 방법이 궁금합니다.

#include <zlib.h>
 
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
 
#include "HDLib.h"
#include "HDList.h"
 
#define NAME_MAX    256
#define BUF_MAX     1024
 
#define ClearReadBuffer() while(getchar()!='\n')
 
int ArchiveData(gzFile *zfp, const HDList *plist);
 
int main(void)
{
    char ch;
    HDList flist;
    char tmpName[NAME_MAX];
 
    gzFile *zfp;
    int fd;
 
    // Initialize list
    HDListInit(&flist);
 
    // Get File Data From Standard Input Stream
    do
    {
        printf("0. Make file\n");
        printf("1. Add files to list\n");
        printf("2. Show added file's list\n");
        printf("3. Archive data\n");
        printf("4. Extract File\n");
        printf(">> ");
        scanf("%c", &ch);
        ClearReadBuffer();
 
        switch (ch)
        {
            case '0':
                printf("Enter the name you want: ");
                scanf("%s", tmpName);
                if (access(tmpName, F_OK)==0)
                {
                    printf("Error: Already exists\n");
                    break;
                }
                if (!fopen(tmpName, "wb"))
                {
                    printf("Error: Cannot create file named %s\n", tmpName);
                    break;
                }
                break;
 
            // Add files to list
            case '1':
                printf("Enter the name of target: ");
                fgets(tmpName, NAME_MAX, stdin);
                tmpName[strlen(tmpName)-1]=0;
//                printf("File's name: %s\n", tmpName);
 
                // Check the original file exists
                if (access(tmpName, F_OK)!=0)
                {
                    printf("Error: File %s does not exist\n", tmpName);
                    break;
                }
                fd = open(tmpName, O_RDONLY);
                if (fd<0)
                {
                    printf("Error: Cannot open file %s\n", tmpName);
                    break;
                }
                HDListAddValue(&flist, fd);
                break;
 
            // Show added file's list
            case '2':
                printf("Number of file: %d\n", flist.len);
                HDListShow(&flist);
                break;
 
            // Archive data
            case '3':
                strcpy(tmpName, "Test.gz");
                zfp = gzopen(tmpName, "wb");
                if (!zfp)
                {
                    printf("Error: Cannot create file %s\n", tmpName);
                    break;
                }
                if (ArchiveData(zfp, &flist))
                {
                    printf("Error: Cannot complete archiving data\n");
                    break;
                }
                gzclose(zfp);
                break;
 
            // Extract File
            case '4':
                break;
 
            // Input error: try again
            default:
                printf("Try again\n");
                continue;
        }
        if (NAME_MAX<=strlen(tmpName))
            ClearReadBuffer();
 
        printf("Try again(y/n)? ");
        scanf("%c", &ch);
        ClearReadBuffer();
 
    } while (toupper(ch)!='N');
 
    HDListDealloc(&flist);
    return 0;
}
 
int ArchiveData(gzFile *zfp, const HDList *plist)
{
    int i;
    int n, lerrno;
    char buf[BUF_MAX];
    HDLNode *pnode = plist->phead;
 
    if (HDListIsEmpty(plist))
        return HDLIST_IS_EMPTY;
 
    for (i=0; i<plist->len; ++i)
    {
        while ((n=(int)read(pnode->data.value, buf, BUF_MAX))>0)
            if (gzwrite(zfp, buf, n)<0)
            {
                printf("%s\n", gzerror(zfp, &lerrno));
                return -1;
            }
        pnode = pnode->next;
    }
 
    return 0;
}