'''print_file function''': Opens a file and prints it line by line
int print_file(char * filename);
int main(int argc, char * argv[]) {
if(argc < 2) { printf("Need File\n"); return -1; }
char * filename = argv[1];
return print_file(filename); }
int print_file(char * filename) { FILE *f; f = fopen(filename, "r");
if(f == NULL) return -1;
const int BUFFER_SIZE = 100; char buffer[BUFFER_SIZE];
while(fgets(buffer, BUFFER_SIZE,f) != 0 ) { printf("%s", buffer); }
fclose(f); return 0 ; }