ssize_t c_write(int fd, const void *buff, int bytesToWrite) {
    size_t bytesWritten;
    for (bytesWritten = 0; bytesWritten < bytesToWrite; ) {
        ssize_t currentlyWritten = write(fd, buff + bytesWritten, bytesToWrite - bytesWritten);
        if (currentlyWritten == 0) {
            return bytesWritten;
        }

        if (currentlyWritten == -1) {
            return -1;
        }
        bytesWritten += currentlyWritten;
    }
    return bytesWritten;
}


ssize_t c_read(int fd, void *buff, int bytesToRead) {
    size_t bytesRead;
    for (bytesRead = 0; bytesRead < bytesToRead; ) {
        ssize_t currentlyRead = read(fd, buff + bytesRead, bytesToRead - bytesRead);
        if (currentlyRead == 0) {
            return bytesRead;
        }

        if (currentlyRead == -1) {
            return -1;
        }
        bytesRead += currentlyRead;
    }
    return bytesRead;
}