/dev/fd driver for Ultrix DECstations

/dev/fd driver for Ultrix DECstations

[John Mackin]

I thought this was posted to comp.sources.unix.  In any case it was
certainly ok'd for public release; I would have given a reference
to comp.sources.unix for it but when I looked I couldn't work out
what was going on there -- maybe the archive site I looked at
was busted.  Anyway.  Since rc can use /dev/fd to advantage,
maybe this will interest people on this list.  As the Subject: says,
this is a device driver implementing /dev/fd for DECstations
running Ultrix, version 4.2 (or later, it says; I have only
tried 4.2 myself).  This is by Boyd Roberts.  You need the
kernel objects that come with your Ultrix distribution to
re-build the kernel to include this driver.  Follow the
build instructions in the README; they work :).

OK,
John.

# To unbundle, sh this file
echo README 1>&2
sed 's/.//' >README <<'//GO.SYSIN DD README'
-Installation instructions for a Ninth Edition style /dev/fd driver for
-4.2 (and later) ULTRIX systems.
-
-    1. cp devfd.c /usr/sys/fs/gfs
-
-    2. Edit /usr/sys/machine/common/conf.c and before `cdevsw' add :
-
-#if	DEVFD > 0
-int	devfdopen();
-#else
-#define devfdopen	nodev
-#endif
-
-    3. Choose a free slot in the `cdevsw' (I used 90) and put:
-
-	{devfdopen,	nodev,		nodev,		nodev,	/*90*/
-	nodev,		nodev,		nodev,		0,
-	nodev,		nodev,		0,		0},
-
-    4. Edit /usr/sys/conf/mips/files.mips and add:
-
-fs/gfs/devfd.c			optional devfd device-driver Notbinary
-
-    5. To enable this driver for your kernel, the following two lines
-       must be added to /usr/sys/conf/mips/<machine>
-
-options		DEVFD
-pseudo-device	devfd
-
-  
-    6. Re-configure your kernel and make it:
-
-	    cd /usr/sys/conf/mips/<machine>
-	    config <machine>
-	    cd /usr/sys/MIPS/<machine>
-	    make depend
-	    make
-
-    7. Boot the new `vmunix'.
-
-    8. Create the necessary special files with /usr/bin/sh5:
-
-	    cd /dev
-	    mkdir fd
-	    cd fd
-	    umask 0111
-	    i=0
-	    while test $i -lt 64
-	    do
-	    	mknod $i c 90 $i	# use major device (ie. 90) that
-	    	i=`expr $i + 1`		# concurs with your cdevsw entry
-	    done
-	    ln /dev/fd/0 /dev/stdin
-	    ln /dev/fd/1 /dev/stdout
-	    ln /dev/fd/2 /dev/stderr
-
-     9. You now have a /dev/fd driver, test it with:
-
-	    echo '/dev/fd ok?' | cat /dev/stdin
-
-Thanks to Norman Wilson for an essential piece of insight which allows /dev/fd
-to be implemented as a driver, rather than a foul hack in the kernel [c]open().
-
-
-Boyd Roberts <boyd@prl.dec.com>
-Member of Technical Staff
-Paris Research Laboratory
-Digital Equipment Corporation
//GO.SYSIN DD README
echo devfd.c 1>&2
sed 's/.//' >devfd.c <<'//GO.SYSIN DD devfd.c'
-/*              Copyright 1991 Digital Equipment Corporation
- *                         All Rights Reserved
- *
- * Permission to use, copy, and modify this software and its documentation is
- * hereby granted only under the following terms and conditions.  Both the
- * above copyright notice and this permission notice must appear in all copies
- * of the software, derivative works or modified versions, and any portions
- * thereof, and both notices must appear in supporting documentation.
- *
- * Users of this software agree to the terms and conditions set forth herein,
- * and hereby grant back to Digital a non-exclusive, unrestricted, royalty-free
- * right and license under any changes, enhancements or extensions made to the
- * core functions of the software, including but not limited to those affording
- * compatibility with other hardware or software environments, but excluding
- * applications which incorporate this software.  Users further agree to use
- * their best efforts to return to Digital any such changes, enhancements or
- * extensions that they make and inform Digital of noteworthy uses of this
- * software.  Correspondence should be provided to Digital at:
- *
- *                       Director of Licensing
- *                       Paris Research Laboratory
- *                       Digital Equipment Corporation
- *                       85 Avenue Victor Hugo
- *                       92500 Rueil Malmaison
- *                       France
- *
- * This software may be distributed (but not offered for sale or transferred
- * for compensation) to third parties, provided such third parties agree to
- * abide by the terms and conditions of this notice.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
- * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
- * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
- * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
- * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
- * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
- * SOFTWARE.
- */
-
-/*
- *	Ninth Edition style /dev/fd/... driver.
- *
- *	Boyd Roberts <boyd@prl.dec.com>
- *	Digital PRL
- *	September '91
- */
-
-#include "../h/param.h"
-#include "../h/systm.h"
-#include "../h/dir.h"
-#include "../h/user.h"
-#include "../h/kernel.h"
-#include "../h/gnode.h"
-#include "../h/proc.h"
-#include "../h/conf.h"
-#include "../h/file.h"
-#include "../h/socket.h"
-#include "../h/socketvar.h"
-#include "../h/mount.h"
-#include "../h/stat.h"
-#include "../h/ioctl.h"
-#include "../h/flock.h"
-#include "../h/exec.h"
-
-#undef	GETF
-#define GETF(fp, fd)	if ((fp = getf(fd)) == NULL) return u.u_error
-
-int
-devfdopen(dev, flag)
-dev_t	dev;
-int	flag;
-{
-	struct file	*fp;	/* file table entry for this open */
-	struct file	*dfp;	/* file table entry for /dev/fd/`minor(dev)' */
-	int		fd;	/* fd allocated for this open */
-	int		dfd;	/* fd allocated for /dev/fd/`minor(dev)' */
-
-	dfd = minor(dev);
-	fd = u.u_r.r_val1;	/* courtesy of ufalloc() */
-
-#ifdef	DEBUG
-	mprintf("/dev/fd/%d will be %d\n", dfd, fd);
-#endif	DEBUG
-
-	GETF(dfp, dfd);
-	GETF(fp, fd);
-
-	/* If both are the same then it's opening a closed /dev/fd/... */
-	if (fp == dfp)
-		return EBADF;
-
-	/* fake dup() */
-	smp_lock(&lk_file, LK_RETRY);
-	U_OFILE_SET(fd, dfp);
-	dfp->f_count++;
-	U_POFILE_SET(fd, U_POFILE(dfd));
-	smp_unlock(&lk_file);
-
-	/* free my file table entry and return */
-	return closef(fp);
-}
-
//GO.SYSIN DD devfd.c

Re: /dev/fd driver for Ultrix DECstations

[Scott Schwartz]

Does anyone have one for SunOS, by any chance?

Re: /dev/fd driver for Ultrix DECstations

[Jim Davis]

On Mon, 29 Mar 1993, Scott Schwartz wrote:
> Does anyone have one for SunOS, by any chance?

Yes, for 4.1.1.  Never tried it on 4.1.2 or 4.1.3, but I think it should
work.  Anonymous ftp to gemini.tuc.noao.edu:/pub/devfd.shar.

(For all its warts, Solaris 2.1 has /dev/fd built in and it works well
with rc.)
--
Jim Davis               | "So here I am, not being entertained."
jdavis@cs.arizona.edu   |   -- Calvin