Parallel SHA-512 Cracker

/*
*   Parallel SHA-512 Password Cracker with OpenMP
*   Compile:    gcc -fopenmp -lcrypt -std=c99 -o parshacrk parshacrk.c
*   Written by: JaKo
*   Date: 16/11/2015
*/
#include <stdio.h>
#include <string.h>
#include <crypt.h>
#include <stdlib.h>
#include <omp.h>

void chop(char *word){
  int lenword=strlen(word);
  if(word[lenword-1] == '\n')   word[lenword-1] = '\0';
}

int numlines(FILE *file){
    if(file==NULL)  return -1;
    char ch;
    int lines = 0;
    while (ch != EOF){
        ch = fgetc(file);
            if(ch == '\n')  lines++;
    }
    return lines;
}

void main(int argc, char *argv[]){
  //Parameters error handling
  if(argc!=4){
    printf("Parallel SHA-512 Password Cracker\nUSAGE: ./parshacrk <PATH TO DICTIONARY> '$6$<SALT>$' '$6$<SALT>$<SHA-512 HASH>'\n");
    exit(-1);
  }
  int found=0;  //0 = password not found ; 1 = password found
  char word[BUFSIZ],salt[BUFSIZ], pwhash[BUFSIZ];
  FILE *words = fopen(argv[1],"r"); //Open dictionary file
  //File error handling
  if(words==NULL){
    printf("Cannot open dictionary file.\n");
    exit(-1);
  }
  strcpy(salt,argv[2]);
  strcpy(pwhash,argv[3]);
  int size = numlines(words); // Number of words in dictionary
  if(fseek(words,0,SEEK_SET)==-1)   exit(-1);   //seek error handling
  //Parallel Region
  #pragma omp parallel for private(word) shared(found) schedule(dynamic)
  for(int i=0;i<size;i++){
    if(fgets(word,BUFSIZ,words) != NULL){
        chop(word);
        if(found==1)    exit(1);
        printf("[*] THREAD %i TRYING: %s\n",omp_get_thread_num(),word);
        char *hash = (char*)crypt(word,salt);
        if(strcmp(hash,pwhash) == 0){
            printf("[+] PASSWORD FOUND: %s\n",word);
            found=1;
        }
    }
  }
  fclose(words);
  if(found==0)  printf("[-] PASSWORD NOT FOUND, EXITING...\n");
  exit(0);
}