Re: Selects on dirs/files.

["N. Jason Kleinbub" <jkleinbub@navtechinc.com>]

Manfred Spraul wrote:

 > "N. Jason Kleinbub" wrote:
 >> People,
 >>
 >> Not sure where to go from here but ....
 >>
 >>         ( Yes I have read the FAQ )=
 >>
 >> For practical reasons, I have created some modification to the
 >> Linux kernel.  These changes were to make our implementation of
 >> software more convenient (elegant).  Essentially, I have modified the
 >> select() calls to allow the non-trivial use of directories as an 'fd'.
 >>
 > Have you checked the F_NOTIFY fcntl()?
 >
 > If yes, what's the difference between your patch and F_NOTIFY?

The biggest impediment that I saw with F_NOTIFY was the inability
to distinguish _which_ directory generated the signal.  This was
especially problematic for multithreaded apps.  Also I would have
a chance of missing the signal if they pile ontop of each other.
Everytime I was interupted from my sleep() by a signal I would
have to scan _each_ directory to find the next file.

I admit, however, that the current F_NOTIFY has more functionality
then the current select().

Plus, for our programmers, it is a stylistic choice.  They prefer,
and better understand, using select()/poll() versus signal io.