readlineWithPrimitive

ssize_t readLine(char *buffer, char *filename, int size, off_t *offset) {
    int fd = open(filename, O_RDONLY);

    if (fd == -1) return -1;

    ssize_t charCount = 0, counter = 0;
    char *p = NULL;
    if ((charCount = lseek (fd, *offset, SEEK_SET)) != -1) {
        charCount = read (fd, buffer, size);
    }

    close(fd);
    if (charCount == -1) return -1;

    p = buffer;
    while (counter < charCount && *p != '\n') p++, counter++;

    *p = 0;
    if (counter == charCount) {
        *offset += charCount;

        return charCount < (ssize_t)size ? charCount : 0;
    }

    *offset += counter + 1;

    return counter;
}