Talk:Device node
socket device files
[edit]Can someone add socket device files like /dev/log, /dev/gpmdata, etc.? I would do it by myself, but I almost know nothing of them. --Gronau 11:35, 15 April 2006 (UTC)
- "A device node, device file, or device special file is a type of special file used on many Unix-like operating systems." So named pipes (FIFOs) and Unix domain sockets (local sockets) don't belong here unless we widen the scope of this article. I wouldn't suggest that because they are just forms of inter-process communication (IPC). The different file types are listed at File system permissions#Symbolic notation. --TuukkaH 18:39, 15 April 2006 (UTC)
- If it has '/dev' in it, it belongs here. Poppafuze (talk) 21:06, 15 May 2008 (UTC)
Character versus block devices
[edit]The article stated that the primary difference between block and character device files lies in serial ("one byte at once") vs parallel ("several bytes at once") communication with the underlying device, and buffering of data. In reality, the former is confusing and not necessarily accurate (given that SATA disks use block devices, and parallel port printers use character devices), and the latter is probably not the most important defining quality (and for pseudo-devices, hard to define).
In practice, the most common distinguishing feature between block and character devices is that the latter are used almost exclusively to communicate using position-less byte-stream protocols, where random access to data or seeking is not possible and would make no sense (PRNGs, modems, keyboards, mice); whereas block devices are used to access addressable / positional data such as logical disk surface, memory regions, and so on, where random or semi-random access is very much possible and desirable.
I changed the wording to reflect this, just wanted to make a note of the reasoning behind this. --lcamtuf 22:25, 4 July 2007 (UTC)
major/minor number
[edit]I didn't understand the explanation of major and minor numbers. I'm thinking a simple example might go a long way here in helping the reader to understand what's being referred to. —Preceding unsigned comment added by Triple333 (talk • contribs) 17:31, 28 May 2008 (UTC)
/dev/hd* in Fedora >= 7
[edit]The article suggests that the /dev/hd* devices are no longer used in Fedora 7 + and possibly other distributions. The provided citation does not back this up, and in fact references /dev/hd* several times.
I think the author of this statement is possibly confusing the fact that in recent kernels, some devices might be handled by the SATA device drivers that interface via the SCSI block devices (and therefore are exposed via /dev/sd*); and that some devices that previously were being serviced by an ATA driver are now being handled by the new ones, meaning they moved from hd* to sd*. This is not a blanket change however.
anon, 11:37, 19 February 2008 (UTC)
- I think IDE/PATA devices can also be accessed via the "SCSI generic" layer, so they show up as /dev/sda, /dev/sdb. I think this is also done for example by OpenSUSE. Tizio 13:10, 4 March 2008 (UTC)
Merger Proposal
[edit]Due to overlap of useful information in the device node, device file, and devfs pages, I'm proposing a merger to device file system. An alternative suggestion would be to orthogonalize these articles. Poppafuze (talk) 21:18, 15 May 2008 (UTC)