NetWare SMP style worm screensaver for Linux using ncurses

• Overview
• Quick Start Guide
• Building the Screensaver from Source
• Installing and Uninstalling the Screensaver from Source
• Running the Screensaver
• Installing the Screensaver in the Bash Shell
• ssh client returns "unknown terminal type" when remotely logging into the system
• Using Libraries
• Building the Screensaver as an RPM Package (Redhat/CentOS/SuSe)
• Building the Screensaver as a Debian Package (Debian/Ubuntu)
• Issues / Problems / Help

This code is Copyright(c) Jeff V. Merkey 1997-2022 and some portions were adapted from xscreensaver loadsnake program and those portions are Copyright (c) 2007-2011 Cosimo Streppone [email protected].

This software is licensed under the MIT/X License.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

USAGE:  netware-worms [cpus|speedup]
    i.e. worm cpus=<num=8 to 256> speedup=<divisor=1|2|3|4>
examples:
    netware-worms cpus=8;
       start worm screensaver with 8 worm threads
    netware-worms speedup=4
       run worm screensaver at 4X speed

This screensaver is built as both a dynamic shared object (*.so) and static archive (*.a) library module which allows other user space programs and consoles to invoke this screen saver as well as tmux, screen, and other BASH type programs setups.

This screensaver uses ncurses and is text based which is identical to the Novell Netware SMP multi processor screensaver which displayed a color coded worm for each processor running. As each processor load increases on a particular processor, the longer the worm becomes and the faster it moves across the screen corresponding to that particular processor. As the overall system load average across the system increases, the base clock rate for all the worms increases slightly to indicate load average is increasing.

You can download precompiled RPM packages and Debian (DEB) packages from the release page for this project, or you can build the program from the git sources.

If you want to build the program from scratch with the git sources rather than use the pre-compiled RPMS and DEB packages, then please skip to the section Building the Screensaver from Source for instructions on how to do this.

Packages are provided in binary and source versions, and can be downloaded and installed directly or rebuilt for a different target architecture such as ARM64. Package types are Red Hat Package Manager (RPM) packages and Debian (DEB) packages for binary installation and Source RPM packages (SRPMS) and Debbuild SDEB packages for source code installation.

RPM and DEB packages for each release include a binary architecture specific package and a source package which can be downloaded and built/rebuilt and which contains the source code.

For example, the release v1.21 contains the following packages in the release section:

• netware-screensaver-1.21-1.el8.src.rpm
• netware-screensaver-1.21-1.el8.x86_64.rpm

• netware-screensaver-1.21-1.sdeb
• netware-screensaver_1.21-1_amd64.deb

To install the binary package with the rpm package manager for x86_64:

rpm -i netware-screensaver-1.21-1.el8.x86_64.rpm

To deinstall the RPM binary package:

rpm -e netware-screensaver

To install the binary package with the Debian dpkg package manager for amd64:

dpkg -i netware-screensaver_1.21-1_amd64.deb 

To deinstall the Debian dpkg binary package:

dpkg -r netware-screensaver

To install the source package with the rpm package manager:

rpm -i netware-screensaver-1.21-1.el8.src.rpm

(Note: rpm installs the source code files in /root/rpmbuild/ as top directory for RedHat and CentOS platforms. SuSe platforms install the source code files in /usr/src/packages/)

To install the source package with the Debbuild package tool:

debbuild -i netware-screensaver-1.21-1.sdeb

(Note: Debbuild installs the source code files in /root/debbuild/ as top directory)

For building or rebuilding RPMS or DEB Packages after you have installed the associated source packages on your platform, refer to the following:

• Building the Screensaver as an RPM Package (Redhat/CentOS/SuSe)
• Building the Screensaver as a Debian Package (Debian/Ubuntu)

You must have the ncurses-devel packages installed in order to make ncurses apps on your system. you can try "dnf install ncurses\*" to get all of the ncurses packages for RedHat and CentOS systems. This version was developed on a Red Hat 7 / CentOS 7 system.

to make, type:

make -f Makefile <enter>

the build process should display:

g++ -g -c -O3  -fPIC -Wall libnetware-screensaver.c 
ar r libnetware-screensaver.a libnetware-screensaver.o  
ar: creating libnetware-screensaver.a
ld -shared -lc -o libnetware-screensaver.so libnetware-screensaver.o  
g++ -g -O3 netware-worms.c libnetware-screensaver.a -Wall -o netware-worms -lncursesw -lpthread -ltinfo

to perform a clean build:

make -f Makefile clean <enter>

should display:

rm -rf *.o libnetware-screensaver.a libnetware-screensaver.so netware-worms

To install:

make -f Makefile install <enter>

should display:

install -m 0755 netware-worms /usr/bin
install -m 0755 libnetware-screensaver.so /usr/lib64
install -m 644 libnetware-screensaver.a /usr/lib64
install -m 644 netware-worms.h /usr/include
ldconfig
ldconfig

To uninstall:

make -f Makefile uninstall <enter>

should display:

rm -vf /usr/bin/netware-worms
removed '/usr/bin/netware-worms'
rm -vf /usr/lib64/libnetware-screensaver.so
removed '/usr/lib64/libnetware-screensaver.so'
rm -vf /usr/lib64/libnetware-screensaver.a
removed '/usr/lib64/libnetware-screensaver.a'
rm -vf /usr/include/netware-worms.h
removed '/usr/include/netware-worms.h'
ldconfig
ldconfig

you can execute the program directly as:

./netware-worms <enter>

you can also add arguments to force number of cpus and a speedup divisor

./netware-worms cpus=8 speedup=4 <enter>

To install the screensaver as a bash program which auto activates, use the program called "screen" coupled with Bash. The "screen" program has support for adding and invoking terminal based screensavers under Bash.

You can install the program on CentOS and RHEL with dnf by typing "dnf install screen" if the program is not installed by default. On Debian based systems you can install the program with "apt-get install screen".

Red Hat based systems can use yum or dnf to install the screen files:

dnf install screen 

Debian based systems can use apt or apt-get to install the screen files:

apt-get install screen 

You should also install at the same time the terminfo and termcap files to support the "screen" terminal type for ncurses to avoid getting "unknown terminal type" errors when attempting to log into the system over ssh.

Red Hat based systems can use yum or dnf to install the terminfo files:

dnf install ncurses-term 

Debian based systems can use apt or apt-get to install the terminfo files:

apt-get install ncurses-term 

You will need to create a .screenrc file in the user home directory (i.e. ~/.screenrc) which contains the following commands:

sample ~/.screenrc file

blankerprg netware-worms
idle 60 blanker

Please note the idle command which specifies how many seconds to delay before invoking the screensaver (in this example it is 60 seconds)

You also need to modify the ~/.bash_profile default bash configuation file to invoke screen by default after login. Add the /bin/screen command to the end of the ~/.bash_profile config file:

sample ~/.bash_profile

# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
	. ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/bin
export PATH
/bin/screen  

It must be the last line in the file since following login, the /bin/screen program will be executed and run as a transparent bash shell.

After you have configured these two files, logout and log back into the system for whichever account you have enabled and the screensaver will auto-activate after 60 seconds of idle time. The only disadvantage to using this method to enable a terminal based screensaver is you will need to type the "exit" command twice in order to logout of the session.

Some older CentOS and Red Hat Enterprise Linux distributions do not properly detect or parse aliased terminal types such as "screen.xterm-256color" when using ssh to remotely access a system that has screen installed and running. This results in an "unknown terminal type" error being returned after logging in. This error can be fixed by changing the ~/.bashrc file for the affected account and add a check for the term type, then export a terminal type that matches one of the supported terminal types in the ncurses-term package.

Add the following to the bottom of the .bashrc file to check the terminal type, then change and export it if necessary.

if [[ "$TERM" == "screen.xterm-256color" ]]; then
   export TERM=screen-256color
fi

The "screen.xterm-256color" terminal type is the most common terminal type seen when this ssh error occurs and it is caused by the ncurses library terminfo and termcap files either not being installed or improperly configured.

If you encounter this error and are running on version CentOS/RHEL 7 or earlier, then edit your .bashrc file to append the terminal type and remap check as shown in the example below:

sample ~/.bashrc

# .bashrc
# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
	. /etc/bashrc
fi

# add the following 3 lines to the end of the .bashrc file  
if [[ "$TERM" == "screen.xterm-256color" ]]; then          
   export TERM=screen-256color                              
fi                                                         

You can also call the screensaver as a library function "netware_screensaver(cpus, speedup)" from another application with your own timer setup, just be sure to link to the "-lnetware-screensaver" .so library in your linker statements or link to the static library "libnetware-screensaver.a"

In order to build the screensaver as an RPM, the program must be compressed into a tar.gz file and the tar.gz file named to match the versioning information contained in the associated .spec file.

Spec files are special files which contain instructions on how to build a particular package from a source code archive. On Red Hat and CentOS systems, RPMS are built in the /root/rpmbuild/ top directory. SuSe systems build RPMS in the /usr/src/packages/ as top directory. These "top directories" will contain BUILD, BUILDROOT, SPECS, RPMS, SRPMS, and SOURCES subdirectories.

The SPECS directory contains the *.spec files used to build RPMS and SRPMS packages. The SOURCES subdirectory will contain the soure code archive file referred to in the *.spec file used to build the RPM package.

See the Quick Start Guide on instructions for installing the source rpm which installs both the .spec file and source archive file (tar.gz) into the rpm build top directory (i.e. /root/rpmbuild/). You should have previously installed the src.rpm file before attempting to build the rpm. You can also manually install the .spec file into the <top directory>/SPECS/ directory and the source code tarball in the <top directory/SOURCES/ directory, then attempt to build the rpm package.

To build the Screensaver using the rpm tool, change directories (cd) into the /root/rpmbuild/SPECS/ directory (/usr/src/packages/SPECS/ for SuSe) and enter the following command:

rpmbuild -ba netware-screensaver.spec <enter>

The program should output the following if the build is successful and verify that the program wrote both the RPMS and SRPMS packages:

Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.oqGyza
+ umask 022
+ cd /root/rpmbuild/BUILD
+ cd /root/rpmbuild/BUILD
+ rm -rf netware-screensaver-1.21
+ /usr/bin/gzip -dc /root/rpmbuild/SOURCES/netware-screensaver-1.21.tar.gz
+ /usr/bin/tar -xof -
+ STATUS=0
+ '[' 0 -ne 0 ']'
+ cd netware-screensaver-1.21
+ /usr/bin/chmod -Rf a+rX,u+w,g-w,o-w .
+ exit 0
Executing(%build): /bin/sh -e /var/tmp/rpm-tmp.JTscEj
+ umask 022
+ cd /root/rpmbuild/BUILD
+ cd netware-screensaver-1.21
+ /usr/bin/make
g++ -g -c -O3  -fPIC -Wall libnetware-screensaver.c 
ar r libnetware-screensaver.a libnetware-screensaver.o  
ar: creating libnetware-screensaver.a
ld -shared -lc -o libnetware-screensaver.so libnetware-screensaver.o  
g++ -g -O3 netware-worms.c libnetware-screensaver.a -Wall -o netware-worms -lncursesw -lpthread -ltinfo
+ exit 0
Executing(%install): /bin/sh -e /var/tmp/rpm-tmp.GtWplM
+ umask 022
+ cd /root/rpmbuild/BUILD
+ '[' /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64 '!=' / ']'
+ rm -rf /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
++ dirname /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
+ mkdir -p /root/rpmbuild/BUILDROOT
+ mkdir /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
+ cd netware-screensaver-1.21
+ '[' -n /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64 -a /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64 '!=' / ']'
+ /usr/bin/rm -rf /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
+ /usr/bin/mkdir -p /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/sbin
+ /usr/bin/mkdir -p /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/bin
+ /usr/bin/mkdir -p /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/include
+ /usr/bin/mkdir -p /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/lib64
+ /usr/bin/make DESTDIR=/root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64 NOCHK=1 LIBDIR=/usr/lib64 INCDIR=/usr/include BINDIR=/usr/bin install
install -m 0755 netware-worms /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/bin
install -m 0755 libnetware-screensaver.so /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/lib64
install -m 644 libnetware-screensaver.a /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/lib64
install -m 644 netware-worms.h /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64/usr/include
+ /usr/lib/rpm/check-buildroot
+ /usr/lib/rpm/redhat/brp-ldconfig
/sbin/ldconfig: Warning: ignoring configuration file that cannot be opened: /etc/ld.so.conf: No such file or directory
+ /usr/lib/rpm/brp-compress
+ /usr/lib/rpm/brp-strip /usr/bin/strip
+ /usr/lib/rpm/brp-strip-comment-note /usr/bin/strip /usr/bin/objdump
+ /usr/lib/rpm/brp-strip-static-archive /usr/bin/strip
+ /usr/lib/rpm/brp-python-bytecompile '' 1
+ /usr/lib/rpm/brp-python-hardlink
+ PYTHON3=/usr/libexec/platform-python
+ /usr/lib/rpm/redhat/brp-mangle-shebangs
Processing files: netware-screensaver-1.21-1.el8.x86_64
Provides: libnetware-screensaver.so()(64bit) netware-screensaver = 1.21-1.el8 netware-screensaver(x86-64) = 1.21-1.el8
Requires(interp): /bin/sh /bin/sh /bin/sh /bin/sh
Requires(rpmlib): rpmlib(CompressedFileNames) <= 3.0.4-1 rpmlib(FileDigests) <= 4.6.0-1 rpmlib(PayloadFilesHavePrefix) <= 4.0-1
Requires(pre): /bin/sh
Requires(post): /bin/sh
Requires(preun): /bin/sh
Requires(postun): /bin/sh
Requires: libc.so.6()(64bit) libc.so.6(GLIBC_2.2.5)(64bit) libgcc_s.so.1()(64bit) libm.so.6()(64bit) libncursesw.so.6()(64bit) libpthread.so.0()(64bit) libpthread.so.0(GLIBC_2.2.5)(64bit) libstdc++.so.6()(64bit) libtinfo.so.6()(64bit) rtld(GNU_HASH)
Checking for unpackaged file(s): /usr/lib/rpm/check-files /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
Wrote: /root/rpmbuild/SRPMS/netware-screensaver-1.21-1.el8.src.rpm
Wrote: /root/rpmbuild/RPMS/x86_64/netware-screensaver-1.21-1.el8.x86_64.rpm
Executing(%clean): /bin/sh -e /var/tmp/rpm-tmp.PbtDr4
+ umask 022
+ cd /root/rpmbuild/BUILD
+ cd netware-screensaver-1.21
+ /usr/bin/rm -rf /root/rpmbuild/BUILDROOT/netware-screensaver-1.21-1.el8.x86_64
+ exit 0

In order to build the screensaver as a Debian package, the program must be compressed into a tar.gz file and the tar.gz file named to match the versioning information contained in the associated .spec file. Spec files are special files which contain instructions on how to build a particular package from a source code archive.

Debian Packages can be built using a utility called "debbuild" and use a top directory structure which is similar to that used by the RPM tool but using /root/debbuild/ as the "top directory". These "top directories" will contain BUILD, BUILDROOT, SPECS, DEBS, SDEBS, and SOURCES subdirectories and follows a similar layout that is used for RPM files.

The SPECS directory contains the *.spec files used to build DEB and SDEB packages. The SOURCES subdirectory will contain the soure code archive file referred to in the *.spec file used to build the DEB and SDEB packages.

See the Quick Start Guide on instructions for installing the source SDEB which installs both the .spec file and source archive file (tar.gz) into the debbuild top directory (i.e. /root/debbuild/). You should have previously installed the SDEB file before attempting to build the DEB package. You can also manually install the .spec file into the <top directory>/SPECS/ directory and the source code tarball in the <top directory/SOURCES/ directory, then attempt to build the DEB package.

To build the Screensaver using debbuild, change directories (cd) into the /root/debbuild/SPECS/ directory and enter the following command:

debbuild -vv -ba netware-screensaver.spec <enter>

The program should output the following if the build is successful and verify that the program wrote both the DEB and SDEB packages:

This is debbuild, version 22.02.1\ndebconfigdir:/usr/lib/debbuild\nsysconfdir:/etc\n
Lua: No Lua module loaded
Executing (%prep): /bin/sh -e /var/tmp/deb-tmp.prep.20277
+ umask 022
+ cd /root/debbuild/BUILD
+ /bin/rm -rf netware-screensaver-1.21
+ /bin/gzip -dc /root/debbuild/SOURCES/netware-screensaver-1.21.tar.gz
+ /bin/tar -xf -
+ STATUS=0
+ '[' 0 -ne 0 ']'
+ cd netware-screensaver-1.21
+ /bin/chmod -Rf a+rX,u+w,go-w .
+ exit 0
Executing (%build): /bin/sh -e /var/tmp/deb-tmp.build.33585
+ umask 022
+ cd /root/debbuild/BUILD
+ cd netware-screensaver-1.21
+ /usr/bin/make
g++ -g -c -O3  -fPIC -Wall libnetware-screensaver.c 
ar r libnetware-screensaver.a libnetware-screensaver.o  
ar: creating libnetware-screensaver.a
ld -shared -lc -o libnetware-screensaver.so libnetware-screensaver.o  
g++ -g -O3 netware-worms.c libnetware-screensaver.a -Wall -o netware-worms -lncursesw -lpthread -ltinfo
+ exit 0
Executing (%install): /bin/sh -e /var/tmp/deb-tmp.install.73931
+ umask 022
+ cd /root/debbuild/BUILD
+ cd netware-screensaver-1.21
+ '[' -n /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64 -a /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64 '!=' / ']'
+ /bin/rm -rf /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64
+ /bin/mkdir -p /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/sbin
+ /bin/mkdir -p /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/bin
+ /bin/mkdir -p /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/include
+ /bin/mkdir -p /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/lib/x86_64-linux-gnu
+ /usr/bin/make DESTDIR=/root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64 NOCHK=1 LIBDIR=/usr/lib/x86_64-linux-gnu INCDIR=/usr/include BINDIR=/usr/bin install
install -m 0755 netware-worms /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/bin
install -m 0755 libnetware-screensaver.so /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/lib/x86_64-linux-gnu
install -m 644 libnetware-screensaver.a /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/lib/x86_64-linux-gnu
install -m 644 netware-worms.h /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/usr/include
+ exit 0
Checking library requirements...
dpkg-query: no path found matching pattern /lib64/libncursesw.so.6
dpkg-query: no path found matching pattern /lib64/libtinfo.so.6
dpkg-query: no path found matching pattern /lib64/libpthread.so.0
dpkg-query: no path found matching pattern /lib64/libstdc++.so.6
dpkg-query: no path found matching pattern /lib64/libm.so.6
dpkg-query: no path found matching pattern /lib64/libgcc_s.so.1
dpkg-query: no path found matching pattern /lib64/libc.so.6
dpkg-query: no path found matching pattern /lib64/libdl.so.2
dpkg-query: no path found matching pattern /lib64/libc.so.6
Executing (package-creation): /bin/sh -e /var/tmp/deb-tmp.pkg.37356 for netware-screensaver
+ umask 022
+ cd /root/debbuild/BUILD
+ /usr/bin/fakeroot -- /usr/bin/dpkg-deb -b /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/main /root/debbuild/DEBS/amd64/netware-screensaver_1.21-1_amd64.deb
dpkg-deb: warning: parsing file '/root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64/main/DEBIAN/control' near line 10 package 'netware-screensaver':
 missing 'Maintainer' field
dpkg-deb: warning: ignoring 1 warning about the control file(s)
dpkg-deb: building package 'netware-screensaver' in '/root/debbuild/DEBS/amd64/netware-screensaver_1.21-1_amd64.deb'.
+ exit 0
Executing (%clean): /bin/sh -e /var/tmp/deb-tmp.clean.95144
+ umask 022
+ cd /root/debbuild/BUILD
+ '[' /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64 '!=' / ']'
+ /bin/rm -rf /root/debbuild/BUILDROOT/netware-screensaver-1.21-1.amd64
+ exit 0
Wrote source package netware-screensaver-1.21-1.sdeb in /root/debbuild/SDEBS.
Wrote binary package netware-screensaver_1.21-1_amd64.deb in /root/debbuild/DEBS/amd64

If you have any issues, please log them at https://github.com/jeffmerkey/netware-screensaver-linux/issues

If you have any suggestions for improvements then pull requests are welcomed, or raise an issue.