setup question

["Jonathan T. Ledlie" <ledlie@xxxxxxxxxxx>]

Hi!  Another Wisconsin student and I are trying to use the SGI RawIO patch to
do some experiments relating to HTTP web caching, and we are not quite sure
how to set it up.  Here's what we've done:
- applied the patch to a 2.2.13 kernel (set the CONFIG_RAW, using make 
xconfig) and booted with it.
- added a raw device with the command:
mknod raw c 8 9
where sda9 was a spare partition on my scsi disk.
[root@calamata raw-prelim]# ls -la /dev/sda*
brw-rw----   1 root     disk       8,   0 May  5  1998 /dev/sda
brw-rw----   1 root     disk       8,   1 May  5  1998 /dev/sda1
brw-rw----   1 root     disk       8,  10 May  5  1998 /dev/sda10
brw-rw----   1 root     disk       8,  11 May  5  1998 /dev/sda11
brw-rw----   1 root     disk       8,  12 May  5  1998 /dev/sda12
brw-rw----   1 root     disk       8,  13 May  5  1998 /dev/sda13
brw-rw----   1 root     disk       8,  14 May  5  1998 /dev/sda14
brw-rw----   1 root     disk       8,  15 May  5  1998 /dev/sda15
brw-rw----   1 root     disk       8,   2 May  5  1998 /dev/sda2
brw-rw----   1 root     disk       8,   3 May  5  1998 /dev/sda3
brw-rw----   1 root     disk       8,   4 May  5  1998 /dev/sda4
brw-rw----   1 root     disk       8,   5 May  5  1998 /dev/sda5
brw-rw----   1 root     disk       8,   6 May  5  1998 /dev/sda6
brw-rw----   1 root     disk       8,   7 May  5  1998 /dev/sda7
brw-rw----   1 root     disk       8,   8 May  5  1998 /dev/sda8
brw-rw----   1 root     disk       8,   9 May  5  1998 /dev/sda9

And then I've tried to run the two follow C programs but, by the looks of the
output, things aren't quite working:

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h> 
#include <unistd.h> 

int main () {
  printf ("hi!");
  int fd = open ("/dev/raw", O_WRONLY);
  if (fd < 2) {
    printf ("bad fd = %d\n", fd);
    exit (-1);
  }
  char *bufOut;
  bufOut = new char [512];
  sprintf (bufOut, "i'm hungry.");
  int writeLen = write (fd, bufOut, 512);
  printf ("fd=%d %d %s\n", fd, writeLen, bufOut); 
  close (fd);
}

***************************************
output:
[root@calamata raw-prelim]# ./write
hi!fd=3 -1 i'm hungry.

**************************************


#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h> 
#include <unistd.h> 

int main () {
  printf ("hi!");
  int fd = open ("/dev/raw", O_RDONLY);
  if (fd < 2) {
    printf ("bad fd = %d\n", fd);
    exit (-1);
  }
  char *bufIn;
  bufIn = new char [512];
  int readLen = read (fd, bufIn, 512);
  printf ("fd = %d readLen=%d %s\n", fd, readLen, bufIn);
  close (fd);
}

******************************************
output:
[root@calamata raw-prelim]# ./read
hi!fd = 3 readLen=-1 

******************************************

Thanks for _any_ suggestions!

-jonathan