Hi All!

        I'm using a RH 5.2 (2.0.36),RTL 1.1 on a P133 64MB Ram
(Dell OptiPlex GXi) machine. I tried the following code , but it's not
working:

#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/mman.h>
#define BASE_ADDRESS (63 * 0x100000)
int fd;
int main()
{
        char * data;
        if (fd = open("/dev/mem",O_RDWR) <0)
        {
                printf("\nMem open: ERROR");
                exit(0);
        }
        printf("\n Mem open: OK");
        data = (char*) mmap(0,sizeof(char),PROT_READ | PROT_WRITE , 
                                MAP_FILE | MAP_SHARED, fd, BASE_ADDRESS );
        if (MAP_FAILED == data)
        {
                printf("Mapping shared memory: ERROR");
                exit(0);
        }
        /*... some operation with data... */
        close(fd);
        munmap((void *)data,sizeof(char);
}
I tried this following the documentation of Frederick M. Proctor.
The shared mem is initialized to 1M in the lilo.conf (append="mem=63m")).
mmap always returns MAP_FAILED.

Could somebody tell me what could be wrong woth it?

Thanx.                  Christian Fischer, Hungary



--- [rtl] ---
To unsubscribe:
echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR
echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED]
----
For more information on Real-Time Linux see:
http://www.rtlinux.org/~rtlinux/

Reply via email to