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SubjectRe: Fw: select(), EOF...
On Mon, 20 Aug 2001, Carlos Fernández Sanz wrote:

> (sorry if this is a dupe, I haven't seen it come from the list, so I'm
> resending as plain ASCII in case majordomo kills messages with strange
> stuff)
>
> Hi,
>
> I need to do something similar to tail -f.
> I was hoping that select() or poll() would block my process after reaching
> EOF but (as the man says) EOF doesn't cause read() to block so select() and
> poll() both say I can read. The result is (obviously) that my program waits
> actively and uses all the CPU.
> What's the right way of doing this? I assume the kernel provides facilities
> to find out if there is new data to read (other than EOF).
>
> Thanks.

tail -f just alternates between open() and close(), keeping in memory the
current byte offest into the file.

--
Ignacio Vazquez-Abrams <ignacio@openservices.net>

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