如何在 DevC++ 中访问 Zlib.h？

Question

My teacher asked to run the following code

#include <stdio.h>
#include <string.h> // for strlen #include <assert.h>
#include "zlib.h"
int main(int argc, char* argv[])
{

    // original string len = 36
    char a[50] = "Hello Hello Hello Hello Hello Hello!";
    // placeholder for the compressed (deflated) version of "a"
    char b[50];
    // placeholder for the UNcompressed (inflated) version of "b"
    char c[50];
    printf("Uncompressed size is: %lu\n", strlen(a));
    printf("Uncompressed string is: %s\n", a);
    printf("\n  \n\n");
    // STEP 1.

    // deflate a into b. (that is, compress a into b)
    // zlib struct z_stream defstream;
    defstream.zalloc = Z_NULL;
    defstream.zfree = Z_NULL;
    defstream.opaque = Z_NULL;

    // setup "a" as the input and "b" as the compressed output

    defstream.avail_in = (uInt)strlen(a) + 1; // size of input, string + terminator
    defstream.next_in = (Bytef*)a; // input char array
    defstream.avail_out = (uInt)sizeof(b); // size of output
    defstream.next_out = (Bytef*)b; // output char array

    // the actual compression work.

    deflateInit(&defstream, Z_BEST_COMPRESSION);
    deflate(&defstream, Z_FINISH);
    deflateEnd(&defstream);
    // This is one way of getting the size of the output

    printf("Compressed size is: %lu\n", strlen(b));
    printf("Compressed string is: %s\n", b);

    printf("\n  \n\n");

    // STEP 2.

    // inflate b into c

    // zlib struct z_stream infstream;
    infstream.zalloc = Z_NULL;
    infstream.zfree = Z_NULL;
    infstream.opaque = Z_NULL;

    // setup "b" as the input and "c" as the compressed output

    infstream.avail_in = (uInt)((char*)defstream.next_out - b); // size of input

    infstream.next_in = (Bytef*)b; // input char array

    infstream.avail_out = (uInt)sizeof(c); // size of output

    infstream.next_out = (Bytef*)c; // output char array

    // the actual DE-compression work. inflateInit(&infstream);
    inflate(&infstream, Z_NO_FLUSH);
    inflateEnd(&infstream);
    printf("Uncompressed size is: %lu\n", strlen(c));
    printf("Uncompressed string is: %s\n", c);
    // make sure uncompressed is exactly equal to original. assert(strcmp(a,c)==0);
    return 0;
}

I'm using Dev C++ compiler and I'm beginner to using external header files. How do I add zlib in devc++? Or please suggest other ways to execute the program.

Note: I using Windows OS

Answer 1

If the file is not installed, you have to first download it from here: https://zlib.net/

Once you install it and it is on your include path, you can include it:

#include <zlib.h>

Alternatively, you can move it to same directory as your main.c file, then your code should compile. Make sure you move all the required files to the directory, normally the.h file only includes declarations, so you'd need a.c file too.

If you do it this way, you won't need to add any other files. I'd advise against using DevC++, is an old, abandoned IDE that uses a non-standard compiler, if you want to use an IDE, I recommend CodeBlocks, a free and open multi platform IDE.