how to print calculated sha1 mac?

[Sylvain BERTRAND]

Hi,

I've discovered today the great thing that is libgcrypt.
I'm having troubles with displaying the calculated hash though. Below is 
the very simple program I wrote to calculate (and print) the SHA1 hash 
from a given file.
Is this program correct? What can I do to make the hash printable to a 
file or to stdout?
Thank for your help.

Regards,

Sylvain BERTRAND


/* sha1-hash.c */

#include <gcrypt.h>
#include <stdlib.h>
#include <stdio.h>

#define HASH_TYPE GCRY_MD_SHA1

int main (int argc, char ** argv) {
        char * filename = argv[1];
        int c;
        unsigned char *hash;
        gcry_md_hd_t h;
        gcry_md_open(&h,HASH_TYPE,0);
        FILE * file = fopen(filename,"r");
        do {
                c = fgetc(file);
                gcry_md_putc(h,c);
        } while (c != EOF);
        gcry_md_final(h);
        hash = gcry_md_read(h,HASH_TYPE);
        fclose(file);
        gcry_md_close(h);
        /* how to print? */
        return 1;
}