#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <stdbool.h>
#include <string.h>
#define MSGLEN (16)

void checker(bool exp, const char *usrmsg, const char *file, const char *func, const int line){
    if(!(exp)){
        perror(usrmsg);
        fprintf(stderr, "%s %s %d\n", file, func, line);
        exit(EXIT_FAILURE);
    }
}
#define osAssert(exp, usrmsg) checker(exp, usrmsg, __FILE__, __func__, __LINE__);

int main(int argc, char **argv){
    osAssert(2 == argc, "nema dovoljno argumenara");
    int fd = open(argv[1], O_RDONLY);
    osAssert(-1 != fd, "open failed");
    int bytesRead;
    do{
        char buf[MSGLEN];

        osAssert(-1 != (bytesRead = read(fd, buf, sizeof buf)), "read failed");
        if(0 == bytesRead){
            break;
        }
        printf("Read number: %d\n", atoi(buf));
    } while(true);
    close(fd);

    return 0;
}