i92guboj |
11-24-2008 12:12 PM |
Quote:
Originally Posted by dxqcanada
(Post 3352176)
Some character devices are created by certain hardware on your computer.
The Terminal sessions you open utilize character devices ... you sound card, pseudo TTY's used for Telnet ... etc.
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Strictly speaking, the hardware doesn't create anything. Some nodes are static (you can create as many as you wish by hand), but most of them are created by udev. Yes, they are created when you plug hardware, but it's not the hardware which creates them, but udev.
In the past a number of systems have been used to manage this, however with the deprecation of devfs most distros nowadays use udev to automate all this stuff.
Quote:
Originally Posted by kevinalm
(Post 3352453)
If you have to ask what a block or charater device file is, you shouldn't be in /dev.
Sorry if that sounds harsh, but those files allow direct access to almost all your hardware. You can really screw up badly in there. You could... oh for example... wipe a hd partion by writing to the wrong file. The files themselves take up very little space, iirc less than a dozen or two dozen bytes each, don't recall precisely. And if you system is using udev then you need them _all_, because when you boot up only the ones you need are created each time you boot.
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Ditto. A person that has to ask what a character device node is obviously is not prepared to say if a given node is needed or not. It's not harsh, it's just obvious.
Deleting a device node can render your system unusable, and will require a reinstall unless you know exactly what you are doing (and it that case you wouldn't have harmed your system in first place). But there are worse things that can happen if you write into a device node (i.e. like losing all your data, irreversibly). On defective hardware even worse things could happen, though that would be getting a bit paranoid.
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