darlap1_frw01.c

/*Darius Lapunas IF-1/8 darlap1*/
/*darlap1_frw01.c*/

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

FILE *rd;
FILE *wd;

int dl_parse_char(char *nr){
	int ret = 0;
	int tmp = 0;
	int i;
	for(i = 0; nr[i] != '\0'; i++){
		tmp = nr[i] - '0';
		if(tmp > 9 || tmp < 0)
			return 0;
		ret *= 10;
		ret += tmp;
	}
	return ret;
}

void dl_exit(int code){
	fclose(wd);
	fclose(rd);
	exit(code);
}

int main(int argc, char *argv[]){
	int b;
	int br;
	char *arr;
	rd = NULL;
	wd = NULL;
	printf( "(C) 2013 Lapunas Darius, %s\n", __FILE__ );
	if(argc != 4){
		printf("1 argumentas - failas skaitymui\n2 argumentas - failas rasymui\n\
3 argumentas - kiek baitu kopijuot\n");
		dl_exit(1);
	}
	rd = fopen(argv[1], "r");
	if(rd == NULL){
		printf("Nepavyko atidaryti pirmo failo\n");
		dl_exit(1);
	}
	wd = fopen(argv[2], "w");
	if(wd == NULL){
		printf("Nepavyko sukurti antro failo\n");
		dl_exit(1);
	}
	b = dl_parse_char(argv[3]);
	if(b == 0){
		printf("Netinkamas baitu skaicius\n");
		dl_exit(1);
	}
	arr = malloc(b);
	br = fread((void*)arr, 1, b, rd);
	if(br == 0){
		printf("Failas tuscias\n");
		dl_exit(1);
	}
	else if(br == -1){
		printf("Nepavyko perskaityti failo\n");
		dl_exit(1);
	}
	fwrite((void*)arr, 1, br, wd);
	dl_exit(0);
	return 0;
}