Thread: Easy mmap question

So I have this write function that writes a byte. The fact that it is JNI is not important:

Code:

JNIEXPORT jint JNICALL Java_com_nextbus_signcontroller_mvc_TechnologicHAL_mmapWriteByte
  (JNIEnv *env, jclass obj, jint address, jbyte value)
{
    /* Use mmap() to map memory, then write byte to address */
    off_t page;
    volatile unsigned char *start;
    int ret;
    int fd;

    fd = open("/dev/mem", O_RDWR);
    if (fd == -1) return -1;
    page = address & PAGE_MASK;
    start = (unsigned char*)
        mmap(0,getpagesize(),PROT_READ|PROT_WRITE,MAP_SHARED,fd,page);
    if (start == MAP_FAILED) {
        close(fd);
        return -1;
    }
    *(start + (ADDR_MASK & address)) = value;
    ret = munmap((void*)start,getpagesize());
    close(fd);
    return ret;
}

I want this to become a 32-bit write operation

My question is this: is changing this to a 32-bit write operation as easy as changing the 'value' parameter from a jbyte to a jint? How would this work if it were not JNI?
Thanks for any info!
Alex