I'm confused a bit ? What are those raw devices ?
The mentioned article says :
> A raw device is one whose accesses are not handled through the caching
> layer and whose actions are immediately and always synchronous with the
> "hard" data on the disk or elsewhere.
How is this different from normal devices ?
I did a small test :
(2) fd=open("/dev/cdrom",O_RDONLY);
read(fd,buffer,1);
wait_a_second();
read(fd,buffer,1);
When the second read is done , the CD-drive spins the CD up and the drive LED
blinks. No sign of caching. ( kernel v2.2.12 )
And even if there were, using the O_SYNC flag should tell the driver :
"Don't cache this , dude !" and there is no need for new device files.
A related question : Why are accesses to devices ( /dev/cdrom and /dev/fd0 are
the ones I tested ) NOT cached ?
Am I missing something important ?
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