                      Release Notes PN 93000359_AE

                 Digi RealPort Driver Package for Linux
                            dgrp-1.9-45.tgz
                            dgrp-1.9-45.src.rpm
                            dgrp-1.9-45_debiansourcepkg.tgz

                       Tested Linux Distributions:
                   Red Hat Enterprise Linux 9.7, 10.1
                            SuSE Leap 16.0
                          Debian 12.12, 13.2
                 Ubuntu (HWE Kernel) 2022.04.5, 2024.04.3


                         Linux Kernels supported:
                            2.4.x (UP and SMP)
                            2.6.x (UP and SMP)
                            3.x.x (UP and SMP)
                            4.x.x (UP and SMP)
                            5.x.x (UP and SMP)
                            6.x.x (UP and SMP)

                        Part Number 40002086_AE

                              02/11/2026


  CONTENTS
  
  Section    Description
  1          Introduction
  2          Supported Products
  3          Image Checksums
  4          Enhancements
  5          Bug Fixes
  6          Known Limitations
  7          Additional Information
  8          History



  1. INTRODUCTION    

     Digi RealPort Linux is a driver package for Digi's Ethernet-based
     Serial Products.
     
     It is assumed that TCP/IP is running on the system and is properly
     configured.
     
     It is also useful, though not necessary, for the tk package to
     be installed, or some other TCL interpreter, in order to use the
     RealPort Manager configuration tool.
     
     It is currently supported on the following hardware platforms:
     
     o Standard i386/i486 and Pentium PC (x86 32bit)
     o x86 64bit
     
     and is currently supported on the following Linux distributions:
     
     o Red Hat Enterprise Linux 9.7, 10.1
     o OpenSuSE Leap 16.0
     o Debian 12.12, 13.2
     o Ubuntu (HWE Kernel) 2022.04.5, 2024.04.3
     
     NOTE: Because of the rapid rate of releases from each respective
           Vendor, the tested/supported list above quickly becomes
           out of date.
           
           This driver package has been tested and verified working for
           kernels through 6.18.4
           
           It is anticipated that this driver will work with Vendor kernel
           releases newer or older than the above but cannot be guaranteed 
           because each respective Vendor can, and does, add their own various
           changes/patches to the stock kernel.org kernel.
           
           These additional Vendor patches to the stock kernel.org linux
           kernel can cause unforeseen incompatibilities with this driver.
     
     Please reference the following number(s) when searching the Digi
     International web site (www.digi.com) or ftp site (ftp.digi.com)
     for the latest software package:
     
     RPM Part Number: 40002086_AE


  2. SUPPORTED PRODUCTS

     Digi Connect Family
     Digi ConnectPort Family
     Digi One Family
     Digi CM Family
     Digi Passport Family
     Digi PortServer TS Family

  3. IMAGE CHECKSUMS
     ${CHECKSUMS}

  4. ENHANCEMENT

     o Support compilation with GCC 14

     o Add support for 6.16 kernels
     
     o Add native systemd unit files
     
         o The RPM and Debian packages now require systemd and will install
           the unit files in the appropriate location
     
         o If installing from source either install the pkg-config package before
           running configure to detect the proper install directory or supply
           the directory with the --with-systemdsystemunitdir=<DIR> option
           to the configure script

  5. BUG FIXES

     o Purge of Debian package now properly removes configuration and
       saved certificates

     o Fix support for kernels 6.1-6.5

  6. KNOWN LIMITATIONS

     o Only DEB and RPM packaging systems are supported as "packaged"
       installation.

     o To build the dgrp driver you must have first loaded the matching
       kernel headers, kernel build tools for your distribution. 

     o To verify that you have matching kernel source, make sure that the
       symbolic link in /lib/modules resolves to a real existing directory:
              readlink -f /lib/modules/$(uname -r)/build


     o Occasionally, a Linux Vendor will ship a kernel that simply cannot
       be autodetected to add the various changes that might be required
       for that specific kernel.  Because of this, there is an option that
       can be used for both the srpm and tgz to tell the driver package
       exactly what distribution you have.

       Currently, the only needed and recognized option is for
            Red Hat AS/ES/WS 3 and Fedora
       The flags are:
            REDHAT_AS_3 / REDHAT_ES_3 / REDHAT_WS_3
            FEDORA

       Examples:

       To tell the srpm that you have Red Hat AS 3, run this instead:

            o rpmbuild --rebuild --define DISTRO=REDHAT_AS_3 40002086_AE.src.rpm

       To tell the tgz that you have Red Hat AS 3, run this during the  
       "configure" phase:

            o ./configure DISTRO=REDHAT_AS_3


     o There is a known incompatibility between our driver and the
       Red Hat 7.1 distribution which ships a custom modified 2.4 kernel.
       The problem manifests itself with device driver usage counts which
       never decrease, possible loss of use of some numbers of ports,
       and possible system instability.  The root cause is in the
       modification of the kernel, which makes a change to an internal
       interface and introduces an incompatibility.

     o There is a problem with the SBRK ioctl.  When a BRK is 
       sent no more data is transmitted until the port is closed.

     o The ports on EM modules are observed to perform at a slightly
       reduced speed during throughput testing.

     o The ditty PRINTER option is not yet supported.
     
     o If this RealPort driver package detects that the system's OpenSSL
       layer is too old to be used reliably, the driver will compile its own
       more current version of OpenSSL. This compile could take a considerable
       amount of time, anywhere from 5 to 60 minutes extra. The extra time it
       takes depends upon how fast of system the driver is being compiled on.

     o The TCP User Timeout option is only supported on kernels >= 2.6.37

     o Shared secret authentication is only supported on kernels >= 2.6.29
     
     o dgrp_gui requires Tcl/Tk version >= 8.6
     
     o When using udev to create devices the permissions passed to
       dgrp_cfg_node do not take effect. Permissions should be set using
       additional custom udev rules files


  7. ADDITIONAL INFORMATION

     o This driver is distributed in three formats: as source RPM and Debian
       packages, and as a compressed tar file of the source code.

     o If you install the source RPM version of the source, it is usually
       as easy as running the following:

           1. rpmbuild --rebuild 40002086_AE.src.rpm
           2. cd ~/rpmbuild/RPMS/x86_64
           3. sudo rpm -i dgrp-1.9-45.x86_64.rpm

     o If you install the compresed tar version of the source, it is usually
       as easy as running the following:

           1. tar xvfz 40002086_AE.tgz
           2. cd ./dgrp-1.9
           3. ./configure
           4. make all
           5. sudo make install
           6. sudo make postinstall

      o To install the Debian Source package

           1. Make and switch to a clean working directory, e.g:
              mkdir work
              cd work
           2. Unpack the Debian source package files for the driver:
                tar -xvzf 40002086_AE_debiansourcepkg.tgz
              to get:
                README
                dgrp_1.9.45.orig.tar.gz
                dgrp_1.9.45-1.dsc
                dgrp_1.9.45-1.debian.tar.xz
           
           3. Build the Debian binary package customized for your environment
                dpkg-source -x dgrp_1.9.45-1.dsc
                cd dgrp-1.9.45
                debuild --no-lintian -b -uc -us
           
              This should create dgrp_1.9.45-1_amd64.deb in the
              parent directory.
           
           4. Install the new Debian binary package
              # Note the leading "../" to fully specify the file pathname
                sudo dpkg -i ../dgrp_1.9.45-1_amd64.deb

     o This package includes several support utilites:

           o ditty                 - an stty replacement.
           o dinc                  - a cu/tip replacement.

     o There is a package of configuration tools provided that are,
       by default, located in the /usr/bin/dgrp/config directory.
       There are scripts for using the command line to add and remove
       products, as well as the RealPort Manager.  
       This is essentially a graphical front end for the scripts and a
       visual tool for monitoring individual serial ports.

    o The software package includes two startup scripts in either the
      /etc/rc.d/init.d or /etc/init.d directories named "dgrp_daemon" and
      "dgrp_ditty".
      These scripts will be executed at startup automatically if the
      "chkconfig" tool is present on the system during the post installation
      phase of the driver install.  Otherwise, these scripts must be manually
      added to the system startup.

    o To load and initialize the driver by hand, execute "dgrp_daemon start".
      To stop the driver daemons and unload the driver, execute
      "dgrp_daemon stop" followed by "rmmod dgrp".


    o The following manpages are provided:
          ditty-rp(1), 
          drpd(8), 
          dgrp(8),
          dgrp_cfg_node(8), 
          dgrp_gui(8). 

    o Red Hat 7.1 -- Kernel Compatibility Issues
         Some 2.4 kernel-based distributions (Red Hat 7.1 included)
         have a patch applied to them which modifies the behavior of
         Linux when an open of a serial port is canceled (for instance,
         if an application is waiting for the carrier signal and a user
         hits CTRL-C to kill the application)

         With this behavior change, the device driver is unable to
         cleanup its internal data structures and the sane functioning
         of the driver is compromised.  The classic symptom of this
         problem is that the command "lsmod", which (among other things)
         will return a count of the applications using the device driver,
         will return a non-zero value even if all applications associated
         with the serial ports are killed.

         Unfortunately, it is impossible (from within the device driver)
         to determine which behavior is implemented in the running kernel.
         However, Digi now provides a workaround to allow customers with
         this problem to change the Digi behavior to be compatible with
         these "patched" kernels.

        To enable the change which provides alternate behavior when a
        serial "open" call fails, execute the following after the device
        driver is loaded:

            echo "alt_fail_open=1" > /proc/dgrp/info

        To return to the standard behavior, execute:

            echo "alt_fail_open=0" > /proc/dgrp/info

        To examine the current state of this driver tuning variable:

            cat /proc/dgrp/info

       Unfortunately, this command must be executed each time the device
       driver is loaded (i.e. when the system is booted).  To make this
       process easier for customers, the Digi standard driver startup
       tools will execute the command on the customer's behalf when it
       loads the driver if the following command is executed:

           touch /usr/bin/dgrp/config/alt_fail_open

       This command will create a file in your file system.  The Digi
       tools, if they detect the existence of this file, will enable the
       "alt_fail_open" behavior on your behalf at every system boot.

    o Running the Realport (dgrp) driver on UEFI/SecureBoot systems.

         If your system generates a "Required key not available"
         message when trying to load the Realport (dgrp) driver, then
         you are probably running on a UEFI system with the SecureBoot
         option enabled.  If you don't actually require the Secureboot
         functionality, the simplest soluion is to boot into the UEFI
         setup menu (typically by pressing a special key like F2 when
         the system first boots) and disable SecureBoot, after which
         your locally compiled kernel modules such as the dgrp driver
         should load and run properly without further effort.
         
         If you wish to keep SecureBoot enabled on your system, then you
         will need to sign kernel modules that you compile locally (such
         as the dgrp driver) with a Machine Owner Key (MOK).  Details:
         
         
         Step 1. Does your system generate a "Required key not available"
                 error message when trying to load the dgrp driver?
         
                 If not, no further set up action is required on your
                 system; the dgrp driver should load and operate normally.
                 Go to Step 5.
         
         
         Step 2. Have you previously created a Machine Owner Key (MOK)
                 for your computer and do you still have access to its
                 corresponding .der and .priv files?
         
                 If yes, skip to Step 3.
         
                 If no, create a new MOK with openssl.  For example:
         
                      openssl req -new -x509 -newkey rsa:2048 \
                           -keyout MOK.priv -outform DER -out MOK.der \
                           -nodes \
                           -days 36500 \
                           -subj "/CN=My_Own_MOK/"
         
                 will create two files -- MOK.der and MOK.priv -- which
                 define your new machine owner key.
         
                 You can replace "36500" with the number of days in the
                 future when you want the MOK to expire and "My_Own_MOK"
                 with some identifying text that will help you recognize
                 and distinguish this particular MOK from others when
                 it is presented to you in a menu.
         
         
         Step 3.  Is your MOK already enrolled with your machine's UEFI system?
         
                  To see what MOKs are currently enrolled:
                         mokutil --list-enrolled
                     or, for an abbreviated version:
                         mokutil --list-enrolled | grep "Subject.*CN"
         
                  Is your MOK already enrolled with your UEFI system?
                  If so, skip to Step 4.
          
                  If not, registering a new MOK with your UEFI and boot
                  loader is a three part process:
          
                     a. Mark the MOK with an import request
         
                           sudo mokutil --import MOK.der
         
                        This will request you to supply a password to
                        be used to unlock the MOK during the next step.
          
                        You can confirm that the new MOK has been imported
                        and is pending enrollment with:
         
                           sudo mokutil --list-new | grep "Subject.*CN"
          
                     b. Then, on the next reboot you should be presented
                        with the UEFI MOK Management screen (watch
                        carefully since it may timeout if no action is
                        taken) which will allow you to view and optionally
                        enroll the pending MOK.  View and enroll your new
                        key (this will prompt for the password you created
                        in step "a") to complete the MOK enrollment.
          
                     c. Once the MOK has been accepted, the UEFI MOK
                        Management screen will advise you that a
                        subsequent reboot is required.  This time the
                        system should boot directly into Linux.
          
                  Once the Linux system is back up, confirm that your
                  new MOK has been enrolled with:

                      mokutil --list-enrolled | grep "Subject.*CN"
         
         
         Step 4.  Sign the dgrp module with your machine owner key (MOK).
         
                  Assuming that your MOK.der and MOK.priv files in the
                  current directory ("./"), sign the dgrp module using the
                  "sign-file" script distributed with your kernel.
                  For example:
         
                     #Ubuntu 16 and similar systems
                     sudo /usr/src/linux-headers-$(uname -r)/scripts/sign-file \
                           sha256 ./MOK.priv ./MOK.der $(modinfo -n dgrp) 
         
                     #RHEL 7 and similar systems
                     sudo /usr/src/kernels/$(uname -r)/scripts/sign-file \
                           sha256 ./MOK.priv ./MOK.der $(modinfo -n dgrp) 
         
                  This looks for the "sign-file" script and the "dgrp.ko"
                  module in the expected places for the currently
                  running kernel (hence the "uname -r" and "modinfo -n"
                  in the invocation).
         
                  You can confirm that the dgrp module has been signed with
         
                      tail -c 100 $(modinfo -n dgrp) | od -c
             
                  which should now report "Module signature appended".
         
         
         Step 5.  Proceed normally.
                  You should now be able to load and run the dgrp
                  driver and utilities such as "dgrp_gui" normally
                  (without "Required key not available" error messages).
         
         Known problems
         --------------
         - As of this writing, Centos 7.5 appears to have a shim bug that
           makes it fail to notice when new MOKs are pending enrollment,
           so the MOK Management Screen never appears.  We can sign
           modules with existing MOKs, create new ones and schedule
           them for enrollment, but we cannot actually enroll new MOKs
           under CentOS 7.5  Other distributions including RHEL 7.5,
           Ubuntu 16.04 and OpenSuSE 42.3 work properly and, once a MOK
           is registered with one of them, all, including CentOS 7.5
           can use it.
         
           So, until the CentOS 7.5 bug is fixed, enrollment of new MOKs
           (step 3 above) must be performed on some other OS.  Once a
           MOK is enrolled with the UEFI (a one time process) it can
           used to sign modules on any OS, including CentOS 7.5.

    o Running the Realport configuration GUI (dgrp_gui) under Wayland.

         dgrp_gui is a Tk-base graphical user interface to the Realport
         command line configuration utility, dgrp_cfg_node, originally
         written to run under X.  Newer Linux distributions are moving
         towards replacing (at least as an option) X with Wayland (See
         www.wayland.freedeskop.org), which poses two problems for
         dgrp_gui.

         1. Traditionally we expected dgrp_gui to be run with superuser
            privileges, invoked, for example as: "sudo dgrp_gui".  Wayland
            requires that the main GUI application be run without elevated
            permissions; invoking only non-GUI portions (such as dgrp_gui's
            callouts to dgrp_cfg_node) at elevated permissions.  So, as of
            the *_AA release, dgrp_gui explicitly does the dgrp_cfg_node
            callouts via "sudo".   This means that it *will* run properly
            under both X and Wayland, but if the sudo credentials
            are not already cached (from some previous sudo use) when
            dgrp_gui is started, when it later comes time for the first
            dgrp_cfg_node invocation, the user will be password prompted.
            Once entered, the sudo password will normally be cached,
            so subsequent invocations will not prompt again.

            But a potential cause for confusion is that the initial password
            prompt appears in the terminal window where dgrp_gui was
            invoked, rather than in the TK window, while the latter is
            probably the focus of the user's attention.  So, if you
            start dgrp_gui without elevated privileges, be careful to
            look for the password prompt when it comes time for the
            first callout to dgrp_cfg_node.

            Clumsy workaround: pre-cache your sudo credentials by running
            something else via sudo (e.g: "sudo ls") before starting dgrp_gui.
           

         2. In some Wayland implementations, dgrp_gui graphics don't display
            properly.  It turns out that the root cause is that Wayland
            sometimes doesn't set the display dimensions properly.  This is
            not just a dgrp_gui problem since it also causes reference Tk
            programs like https://tkdocs.com/tutorial/firstexample.html to
            fail in the same way.   Workarounds:

              a. Select X11 display server instead of Wayland at login.

              b. Run dgrp_gui via "ssh -X" from a client running under X11.

              c. Force your dgrp_gui session to use the Wayland reference
                 compositor: "weston".  From a terminal session run
                 "weston --modules=xwayland.so", then click on the "Terminal"
                 icon in the upper left corner to get a command prompt, and
                 then run "dgrp_gui" from there.  This is "almost" a solution
                 – the buttons display and work properly, but the inventory 
                 line displays in a small font and doesn't seem to scale up.
                 Still, it's kinda usable.

              d. Use the CLI tool, dgrp_cfg_node, instead of dgrp_gui.  See
                 the dgrp_cfg_node documentation ("man dgrp_cfg_node") for
                 details, but here are some examples:

                     i. Configure a 16 port Realport device at 192.168.1.201
                        for standard (unencrypted) communication using a "TS"
                        id:
                          /usr/bin/dgrp/config/dgrp_cfg_node init -v -v \
                          -e never TS 192.168.1.201 16

                    ii. To enable encryption on the network connection, use the
                        "-e always" option:
                          /usr/bin/dgrp/config/dgrp_cfg_node init -v -v \
                          -e always TS 192.168.1.201 16

                   iii. Once the device is configured, start the daemon with:
                          /usr/bin/dgrp/config/dgrp_cfg_node -v -v start TS auto

                    iv. Stop the daemon with:
                          /usr/bin/dgrp/config/dgrp_cfg_node -v -v stop TS

  8. HISTORY
  
    o Version 1.9-44
         o Add support for 6.6 kernels
     
         o Add support for RHEL 9.5
  
    o Version 1.9-42
         o Add support for setting minimum TLS version used for encrypted
           connections to TLS 1.2

         o The TLS certificate of the device is now saved on first connect and
           subsequent connections will be rejected if a different certificate is
           provided by the device

         o Add support for shared secret authentication. Requires a 2.6.29 or later
           kernel

         o Add support for setting TCP_USER_TIMEOUT socket option. Requires a 2.6.37
           or later kernel

         o Add support for Debian 11's 5.10 kernel (RP-240/RP-244)

         o Make OpenSSL a dependency for RealPort rather than including it
           in the Digi distributed source file (RP-255)

         o Add support for 6.X kernels (RP-228)
         
         o Fix dgrp_gui reverting settings to default when a device is reconfigured

         o Fix dgrp_gui not attempting to elevate privilege when viewing tty status
           causing no information to be displayed

         o Fix alignment of columns in dgrp_gui

         o Fix dgrp_cfg_node being unable to stop the running daemon if a custom
           TCP port was specified

         o Fix locking to TLS 1.0 when using OpenSSL version < 1.1.0

    o Version 1.9-41
         o Add compatibiilty for RHEL 8.5, kernels up to 5.18
         o Configure script better detects presence of local openssl
         o OFLAGs settings correctly report state

    o Version 1.9-40
         o Add support for 5.X kernels (tested up to 5.5) (RP-142)
         o Fix support for gcc versions >4 (RP-142)
         o Update the in-source openssl package to version 1.1.1d.  (This is
           only used if openssl is not already installed on the Linux host
           when the driver is installed.) (RP-147, RP-151)
         o dgrp_gui was originally written to run under X.  Enhance it to also
           work under Wayland.  See notes under "KNOWN LIMITATIONS" regarding a
           peculiarity.  (RP-153)
         o Deprecate support for obsolete devices (RP-146)
         o Add Debian Source package release format.  (RP-149)
         o Fix problem with rpm builds on RHEL 7.  (RP-126)

    o Version 1.9-39
         o Added IPv6 address driver support for terminal servers (such as
           the ConnectPort TS 16) that provide them.  (RP-99)

         o Added support for newer kernels through (at least) 4.16.  (RP-110)

         o Updated the in-source openssl package to version 1.0.2o.  (This is
           only used if openssl is not installed on the Linux host when the
           driver is installed.) (RP-117)

         o Added "Running the Realport (dgrp) driver on UEFI/SecureBoot systems"
           section to release notes. (RP-116)

         o Fix edge case in port closing code that could lead to a kernel
           lockup.  (RP-113)

    o Version 1.9-38
         o Updated the in-source openssl package to version 1.0.2l.  (This is
           only used if openssl is not installed on the Linux host when the
           driver is installed.) (RP-86)

         o Added support for 4.X kernels.  Tested with Ubuntu 14 and 16's
           4.4.0-81 kernel, Debian 9.0.0's 4.9.0-3 kernel, OpenSuSE 42.3's
           4.4.73.1 kernel, and with a custom 4.11.4 kernel from kernel.org.
           (NPI-489)

         o The 3.10.0-514.el7 kernel used in the new RHEL 7.3 release introduced
           another backport fix related to TTY_CLOSING that caused the Realport
           driver build to fail. (RP-93)

    o Version 1.9-36
         o Fix an installation problem on systems such as RHEL 7 where
           /etc/sysconfig/network exists but does not define a NETWORKING
           environment variable.

         o Fix a driver build problem on newer kernels, which removed
           definitions for TTY_CLOSING (in v3.11) and TTY_HW_COOK_IN (in v3.19).
           Note that Red Hat backported at least some of these definition
           removals into RHEL 7 kernels starting sometime shortly after
           3.10.0-229, so this driver fix is also needed for their newer
           3.10 kernels.

         o Add a description of the rtstoggle option to the ditty man page.

         o Fix a timing vulerability where an application that fast cycles
           many port open/closes could occasionally obstruct a close from
           completing properly, thus leading to a "locked" port.

         o Fix a problem that could cause the dpa.dgrp utility program to
           crash with an arithmetic exception if it happened to catch a port
           during the early stages of an uncompleted open.

         o Fix the default prefix so that builds from the .tgz distribution
           file will properly install man pages to /usr/share/man (rather than
           /share/man).

    o Version 1.9-35
          o Previously there was a time window at the beginning of port
            opens during which "dgrp_cfg_node" could mistakenly conclude
            that the corresponding node was idle.  If "dgrp_cfg_node uninit"
            were called during this window it could crash the kernel.  A new
            detection mechanism has been added to cover these conditions.

    o Version 1.9-34
          o Fix driver build problem on systems (such as RHEL 7) that define
            CONFIG_UIDGID_STRICT_TYPE_CHECKS.

    o Version 1.9-33
          o Added support for the now latest 3.X kernels (from 3.9.0 through
            3.14).

          o Use /tmp/dgrp (rather than /tmp) during installation to avoid
            the unintended side-effect of modifying the permissions on /tmp.

          o Fix an initialization problem where first opens of transparent
            print devices (/dev/pr*) could crash 3.7.0 and newer kernels.

    o Version 1.9-32
         Interim test release

    o Version 1.9-31
         o Added support for 3.X kernels through 3.8.

         o Changed the dgrp udev rules:
              a. Use SYMLINK rather than NAME since the latter causes
                 problems on newer systems.

              b. Add TAG="systemd" so dgrp devices will be recognized
                 on systemd-based distributions (e.g: to start getty's).

         o Updated configure scripts to add support for newer
           distributions.

    o Version 1.9-30
          o Added support for kernels up to 2.6.38

    o Version 1.9-20

          Added support for kernels up to 2.6.28

          Added support for many new versions of distributions.

          Added support for new style "init" scripts in SuSE 11.1

          Fixed very rare data corruption issue when under very high
          loads and multiple PortServers and SMP.

    o Version 1.9-17

          Added support for Red Hat Enterprise 5,

          Added support for Fedora Core 5, 6 and 7.

          Fixed problem with registering our devices with sysfs
          in 2.6.18.

          Fix compile WARNINGs under 2.6.18.

          Fix a problem with the RealPort UDEV script when using
          new versions of UDEV.

          Fix problem on network disconnect/reconnects where
          the port would always bring up DTR/RTS, even in 
          cases where the port had both signals down before
          the network disconnect.

    o Version 1.9-6

          Added support for DPA for RealPort.
          The utility is installed as /usr/bin/dpa.dgrp

          Added support for SYSFS in the 2.6 kernels.

    o Version 1.9-4

          Fixed problem with setting baud rates higher than 38400
          when using the driver on the IBM pSeries (PPC64) platform.

    o Version 1.9-1

          Fixed driver not working under 2.6.10 kernels and higher.

          Fixed problem with adding similar node names to the driver.

    o Version 1.8-1

          Added RTS Toggle support to the driver.

          Added support for the new Alan Cox TTY layer changes in the kernel.

          Added support for Fedora Core 3, Mandriva Linux 10.1

          Added -n option back into the daemon.

          Added more race condition checking in the tty_close
          routine and the input routine.

          Fixed driver not working under 2.6.8 kernels and higher.

    o Version 1.7-1

          Added support for x86 64bit.
          Added support for Fedora Core 1, Core 2.
          Updated SSL version to 0.9.7d
          Removed support for Linux 2.2 kernels.
          Fixed problem with installing from the tar.gz image.
          Fixed problem with major() and minor() symbols not being found
             on very early versions of the 2.4 kernels.
          Fixed problem on setting the following "o flag" settings:
             nl<0/1> cr<0/1/2/3> tab<0/1/2/3> bs<0/1> vt<0/1> ff<0/1>
          Fixed man page of ditty, now correctly describes [-]DTR.
          Fixed dgrp_cfg_node to correctly set device permissions
             when using the -m flag.
          Fixed dgrp_cfg_node to correctly set owner and group
             when both options are selected.
          Fixed dgrp_cfg_node to correctly set WAN line speed.
          Fixed reporting DTR inconsistancy when opening and closing
             the tty ports very rapidly.
          Reworked locking in dgrp_tty_write to fix possible deadlock.
          Fixed possible race condition in tty_close and dgrp_input.
          Added fix to resolve possible false "RealPort protocol error"
             detection.
          Fixed bug on port close.  Port might not have gotten drained
             before the close.

    o Version 1.6-2

          Added support for RealPort with encryption.
          Added support for Red Hat 9, Suse 8.2, Mandriva Linux 9.1.
          Added support in ditty for the "startin" and "startout" options.
          dgipserv - Added support to set unassigned Ethernet address,
              support for setting the tftp server IP address, support for
              setting virtual ports and virtual ports timeouts, and support
              for setting optimize to throughput or latency.
          Fixed "configure" script problem where modversion.h wasn't being
              found in the proper location.
          Fixed include file problem where the driver would not compile
              correctly under some newer versions of the 2.4 kernel.
          Fixed problem with an incorrect assert message being generated.

    o Version 1.5-0:

          Added Transparent print support. Please read the man page for
             "dgrp", under section "Transparent Print" for more information.
          Changed package install to run a "configure" script first
             before trying to compile the driver. The script should catch
             most of the problems that the compile might have beforehand,
             and give a much better description of the problem than a
             cryptic compiler error message.
          Added Support for Red hat 7.3, Suse 8, Mandriva Linux 8.2,
             and Caldera OpenLinux 3.1.1 (server and workstation).
          Fixed off-by-one error in the tbuf parsing.  This bug, although
             very rare, could have caused the kernel to panic, or cause 
             random kernel memory corruption.

    o Version 1.4-0:

          Improved support for Red Hat 7.1 by offering an architecture to
             workaround a problematic kernel patch shipped with that
             distribution.
          Added support for EL-8, EL-16 and EL-32.
          Added the "dgelreset" application, which allows one to reset
             an EtherLite regardless of whether it is running RealPort
             compatible firmware, and without having to specify a
             MAC address.
          Added "MODULE LICENSE" information to the device driver, in
             order to comply with anti-tainting policies in
             newer 2.4 Linux kernels.
          Modified driver to prevent port "hangup" in the event that the
             daemon dies.
          Added TCFLSH handling to "ditty-rp"... previously, the
          "flushin", "flushout", and "flush" options didn't work.
    o Version 1.3-0: 

          Added full support for Digi's EtherLite products which are
             running Digi RealPort compatible firmware, including the 
             EtherLite 2, EtherLite 160, EtherLite 162,
             and the EtherLite 80.
          Fixed a kernel panic if a port is open, `dgrp_daemon stop` is
             executed, and a program then goes to write to the still
             open port.
             Now write returns EIO in that condition.
          Fixed a select(2) problem in kernel 2.2.15 and later
             of 2.2.x kernels which could cause programs like telnet or
             ssh to appear to hang until a key is pressed.
          Fixed a data loss problem which would manifest itself when exactly
             four kilobytes of data were transmitted after a port was
             opened.
          Added /lib/modules/`uname -r`/kernel/drivers/char to the list of
             locations that the kit will test for existence when trying to
             find an appropriate location to install the driver module, in
             response to testing in native 2.4 kernel-based distributions.

    o Version 1.2-2: 

          Increased support for Digi's ethernet-based serial connectivity
             family; including Digi One, EtherLite, and PortServer products.
          Added support for arbitrary integer baud rates via the "ditty-rp"
             utility.
          Detailed information about the type and version of configured
            remote devices was made available via the "/proc/dgrp/nodeinfo"
            file.
          A memory corruption problem which would cause sysem instability
             was eliminated.
          Unexpected pauses and loss in port traffic as a result of a network
             buffer overflow were resolved.

    o Version 1.1-7: 

          Added 2.4 kernel support.
          Removed references to invalid email addresses.
          Driver now handles Red Hat 7.0 (kgcc vs. gcc).
          The GUI tool now displays the DCD signal when viewing ports.
          RealPort ports now match other Linux serial ports for default
             settings, as well as making all port settings "sticky".  As
             a result of this change, CLOCAL is now on by default.
          Configuration scripts remove the "/dev" files if a
             PortServer is unconfigured.
          Only physical line drops are detected as a "hangup" condition...
             the driver would previously treat a change from CLOCAL to -CLOCAL
             as a carrier transition.
          Startup scripts are installed in "/etc/init.d" if
             "/etc/rc.d/init.d" does not exist.
          RPM installation will not "error out" if "chkconfig"
             (a Red Hat tool) does not exist on the system.
          A message was added to the RPM installation to communicate
             to users whether the installation scripts were added or not.
          On newer systems, RPM would inadvertently strip the driver module
             of its symbols, causing it to fail.  The module is no longer
             stripped.

    o Version 1.0-0: 

          Added a new proc file: /proc/dgrp/info.  This file allows one to
             determine the value of a number of state variables associated
             with the driver, including the driver revision.
          Continued refinement of the GUI.  The GUI is now distributed
             as a single file, rather than a collection of tcl files.
          dgrp_cfg_node now does validity checking of its ID and COUNT
             parameters.

    o  Version 0.1-7:

        A first pass at cleaning up the code was completed for beta release.
        All driver build warnings have been fixed.  Appropriate part numbers
            have been correctly placed in the appropriate documents.
        A useful driver revision number is now placed in the console log
            when the module is loaded.

    o Version 0.1-5:

       A minimum break time of 250ms is now enforced.
       A PPP hang problem was resolved.
       Continued enhancements of the packaging.

    o Version 0.1-4:

       Decided to install dgrp.o to the /usr/bin/dgrp directory, and then
       link in the postinstall phase to a suitable /lib/modules/*/misc
       directory.  This avoids the problem of having the path to dgrp.o
       hardcoded in the spec file.

    o Version 0.1-3:

       Added new scripts to autoload the driver on system startup and
       initialize any PortServers configured in /etc/dgrp.backing.store

    o Version 0.1-1:

       Pilot release in January 1999
