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

#define N 10

char *chars="qwertyuiopasdfghjklzxcvbnm0123456789$#%&=!?";

char *
gen_key(int randfd, int len)
{
        char *pw=malloc(len+1);
        int r;

        r=0;

        while (r < len)
                r+=read(randfd,pw+r,len-r);

        for (int i=0; i < len; i++)
                pw[i]=chars[pw[i]%strlen(chars)];

        pw[len]='\0';

        return pw;
}

int
main(int argc, char **argv)
{
        int f;

        if (argc != 2)
        {
                printf("Sintaxe: %s <length>",argv[0]);
                return -1;
        }

        f=open("/dev/random",O_RDONLY);

        if (f < 0)
        {
                perror("open()");
                return -1;
        }

        for (int i=0; i < N; i++)
        {
                char *p;
                puts(p=gen_key(f,atoi(argv[1])));
                memset(p,0,strlen(p));
                free(p);
        }

        close(f);

        return 0;
}