How to get SCSI-Host nr from generic SCSI device?

How to get SCSI-Host nr from generic SCSI device?

Post by Thomas Niederreite » Thu, 10 Jul 1997 04:00:00

can any SCSI-Expert out there help me?
All I want to do is finding to a specific generic device its host,id,lun
and channel.

I found the SCSI_IOCTL_GET_IDLUN very helpful, but this does not output
the least not in a format I understand it.

Here is my simple test-programm:

#include <stdio.h>
#include <scsi/scsi.h>

struct  sg_id {
                long    l1; /* target | lun << 8 | channel << 16 | low_ino << 24
                long    l2; /* Unique id */

Quote:} sg_id;

main() {
int fd;

        fd = open ("/dev/sg0",2);
        ioctl(fd, SCSI_IOCTL_GET_IDLUN, &sg_id);

        printf("l1: 0x%lX l2: 0x%lX\n", sg_id.l1, sg_id.l2);



When I run it I get:

l1: 0x7000000 l2: 0x0

Fine..this means my device /dev/sg0 is ID 0, Lun 0, Channel 0. Very good
so far...but what does the "low_ino" of 0x07 mean?
Is there a way to conclude from the 0x07 to Host 0?

I have run this programm for different devices on linux (all 2.0.x) with
more than one controllers:

-> For different controllers the low_ino changes, with seems to be fine, but
I still dont know which low_ino corresponds to which host!

Thanx for any answer,


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