Re: How can a process easily get a list of all it's open fd?

From: DervishD <raul@pleyades.net>
To: mra@pobox.com, linux-kernel@vger.kernel.org
Subject: Re: How can a process easily get a list of all it's open fd?
Date: Wed, 28 Aug 2002 01:21:45 +0200	[thread overview]
Message-ID: <3D6C0989.mail6E21O4HV@pleyades.net> (raw)
In-Reply-To: <m38z2s1fkj.fsf@khem.blackfedora.com>

    Hi Mark :)

>So what's the "right way" to do it?

    AFAIK, the for loop, with getdtablesize() instead of 'OPEN_MAX'.
I do it that way, but I don't really know if it is the 'right way'(tm).

>I would *love* for there to be an ioctl or some syscall that I could
>pass a pointer to an int and a pointer to an int array, and it would
>come back telling me how many open fd's I've got, and fill in the
>array with those fd's.

    The array should be allocated by the kernel, or the syscall won't
work as expected ;) If you have 2000 fd open and the array whose
address you pass to the ioctl has an smaller size... Anyway, you can
call the ioctl a few times ;)

    Your proposal seems reasonable (unless there is any other way of
doing this portably), but portability will be an issue...

    Raúl