Sponsored Content
Operating Systems AIX Difference between /dev/hdisk and /dev/rhdisk Post 302825147 by MichaelFelt on Sunday 23rd of June 2013 06:38:50 PM
Old 06-23-2013
Basically, for all *NIX systems, filesystems are created and used via block devices, not character devices.

By definition, character devices have a window of 1 char - a driver might buffer that a little bit (so you can unchar(), or back up one byte.

Block devices are, by definition - finite in size (while char devices may be infinite) - and block devices are "seekable". Because they are seekable, an information system, such as a file system can be stored on them.

Note: some device drivers use ioctl() to perform actions similar to seek - hence the confusion. However, the original definition (at least as far back as UNIX v6) was that character devices did not seek.
 

9 More Discussions You Might Find Interesting

1. Solaris

What is /dev/tty /dev/null and /dev/console

Hi, Anyone can help My solaris 8 system has the following /dev/null , /dev/tty and /dev/console All permission are lrwxrwxrwx Can this be change to a non-world write ?? any impact ?? (12 Replies)
Discussion started by: civic2005
12 Replies

2. UNIX for Dummies Questions & Answers

Sending alt-n to /dev/pts/1 from process bound to /dev/pts/2

Hello, i am using finch (unix commandline instant messaging client using libgnt) which is running connected to /dev/pts/1 Now I would like to "remote control" the program by sending the key combinations normally typed on the keyboard from a programm in another shell. So I tried:... (0 Replies)
Discussion started by: mentos
0 Replies

3. UNIX for Dummies Questions & Answers

Difference between /dev and devices

Please explain me the difference between /dev and devices.. Googled info is - /dev - where logical device names stores here devices - physical device info stores here... Could any one explain me.. the real difference and major one (3 Replies)
Discussion started by: VijaySolaris
3 Replies

4. Solaris

Lun remove, stuck in /dev/dsk and /dev/rdsk

So, we removed a LUN from the SAN and the system is refusing to remove the references to it in the /dev folder. I've done the following: devfsadm -Cv powermt -q luxadm -e offline <drive path> luxadm probe All those commands failed to remove the path. The drive stills shows up as <drive... (13 Replies)
Discussion started by: DustinT
13 Replies

5. AIX

Problem in /dev/hd1 and /dev/hd9var

Hello AIXians, I can't boot my AIX, it hangs and stops at the code error: 0518 After searching google, I knew the problem is due to problems in File Systems. So the solution is booting from any bootable media, then run these commands in maintenance mode: #fsck -y /dev/hd4 #fsck -y... (3 Replies)
Discussion started by: Mohannad
3 Replies

6. Shell Programming and Scripting

Automating partitioning setup of /dev/sda on /dev/sdc

Objective: To recreate the partitioning setup of /dev/sda on /dev/sdc How would I parse the below information and initialize variables (an array?) that can be used to build sgdisk commands in a script, regardless of the number of partitions? Something along the lines of: sgdisk -n... (12 Replies)
Discussion started by: RogerBaran
12 Replies

7. AIX

How can I map hdisk# to rhdisk#?

Some storage/disks have been added to an existing AIX 6.1 server. The admin sent me the list of hdisk#'s for the new disks, but I need the corresponding rhdisk# for the same hdisk. (I know from past experience that the rhdisk that maps to an hdisk is not always the same number. For instance,... (5 Replies)
Discussion started by: sbrower
5 Replies

8. Red Hat

Changing grub from /dev/sda to /dev/sdb

Hi, Please suggest steps to change grub from /dev/sda to /dev/sdb, (1 Reply)
Discussion started by: manoj.solaris
1 Replies

9. HP-UX

Dev/urandom and dev/random missing in HP-UX

Hi, In our HP-UX B.11.11. I could not find dev/urandom and dev/random Are all pseudo-devices implemented as device drivers, or in need to run /configure some package to install the package to have dev/urandom. Please help (4 Replies)
Discussion started by: rashi
4 Replies
devices(4)							   File Formats 							devices(4)

NAME
devices, devid_cache, snapshot_cache, mdi_scsi_vhci_cache, mdi_ib_cache, devname_cache - device configuration information SYNOPSIS
/etc/devices /etc/devices/devid_cache /etc/devices/snapshot_cache /etc/devices/mdi_scsi_vhci_cache /etc/devices/mdi_ib_cache /etc/devices/devname_cache DESCRIPTION
The directory /etc/devices is a repository of device-related data. Files in this directory are used to preserve this information across reboots and are created and updated as necessary by the system. There are no administrative actions necessary with respect to files in /etc/devices. Should the contents of a file become corrupted or an update fail, the file can simply be removed. The system re-creates the file as necessary. SEE ALSO
devfsadm(1M), dev(7FS), ddi_devid_compare(9F), ddi_devid_compare(9F) NOTES
Files in this directory do not constitute an API. Files might not exist or might have a different content or interpretation in a future release. The existence of this notice does not imply that any other documentation that lacks this notice constitutes an API. SunOS 5.11 8 Jun 2006 devices(4)
All times are GMT -4. The time now is 11:55 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy