Free virtual software for linux

Virtual Cron is a PHP library that can check whether it is time to run a periodical task. The class can be used to check whether it is time to run a task that must run from time to time.

It creates a control file to keep track the last time the task was scheduled.

The class can check the control file last modification time to determined whether it passed a given period of time since the last time the task was run.

If the given interval time has passed since the last run, the class recreates the control file and returns true to inform the application that is time to run the task again.

Virtual AGC project is a simulation of the Apollo Guidance Computer (AGC) used in the Apollo Command Modules and Lunar Modules in 1968-1972, as well as the Abort Guidance System (AGS) used in the LM.
The project includes an emulated CPU, an emulated display/keyboard (DSKY), the AGCs original executable binaries and machine-readable assembly-language source code (Luminary and Colossus), AGC source code for a CPU validation suite, an AGC assembler, scanned Apollo documentation, and other elements.
The emulated CPU has been designed to be modular and portable, to facilitate incorporation into spacecraft simulations such as lunar-lander simulations.
Enhancements:
- The Apollo 15-17 CM AGC executable ("Colossus 3" a.k.a. "Artemis 072") is available for use in the simulator.
- (Colossus 3 source code is not yet available.) Scans of the Colossus 3 GSOP document are mostly available.
- CM downlink lists are implemented.
- yaAGC/yaAGS debugging is now symbolic, and yaAGC has other new debugging features.
- Building with Cygwin is possible.
- Many updates have been made to LM_Simulator (the IMU simulation).
- There are bugfixes to yaAGCs CPU simulation.
- The mysterious EDRUPT instruction is handled properly.
- Accelerator keys have been added to yaDSKY.

Virtual Collaboratory is a directed discussion forum based on Mailman and Smartarchiver that provides for threaded short and long term discussions.
Virtual Collaboratory includes a calendaring function, integratation with the Elluminate meeting software, document exchange, version control, a research resource center, custom categorizations, FAQs, and the ability to search for users with similar interests.
Enhancements:
- Refactored Plone into three separate products
- Better Elluminate integration
- I18N support via Py-MYCMSs traslate functionality
- Refactored smartarchiver as a py-mycms system
- Easier isntallation through Install Constancts
- Front page Alerts
- BlogPoster blog management system (works with your blog to help groups collaborate on blog content)
- No longer requires specially patched versions of Zope & plone. (Authentications now done through the PyMyCMSUserFolder)
- Virus checking (pyclamav) now supported if pyclamav is installed

Virtual Drum Machine is a simple drum machine.
It works for little endian/linux kind of machines. You may let it work on others machines, but you probably will get troubles with it.
You definitely need oss (or maybe alsa) for sound output, and a posix-like operating system. To let it work on a big endian machine should be painful.
You write a rhythm, then you compile it, then you are able to play it to your sound card or save it to a file.
The Virtual Drum Machine is made of
- the Rhythm Compiler,
- the runtime library.
The Virtual Drum Machine is in the public domain. Who needs a license? money makers? Protection against robbery? let me laugh... Read any text of law, you will see where the robbers reside.
A simple file would look like :
void main_rhythm(void)
{
tempo = 120;
- a
. b
. b
.
- a
.b
- a
.
. b
. b
- a c
. b
}
Install:
Do a "./configure" in the drums directory, then "make", then "make install", it should be alright. You can listen to some examples in the examples/ directory.
Who yo use it?
Write a rhythm. Compile it with "rc". Run the produced program. You are done.
See the examples/ directory to get the point.
When you run an example, try "-h" to get the available options.
It should be self-explanatory.
The rhythm compiler has several options. By running "rc --help", all should be clear.
Technical Details:
The compiler will parse the input file line by line.
If a line starts with "*" or "." (not counting leading white spaces), the whole line is seen as a rhythm line, and is transformed into C code. If not, it is passed as is to the C file.
Beware! You MUST NOT start any C code line by "*" or "."!
You can create as much functions as you want, write any C code you want. But remember that a line starting by "*" or "." is seen as a rhythm line and is translated by "rc" into C code.
You must provide a "void main_rhythm(void)" function, that will be called by the library. It is the starting point of your rhythm. It can be "void main_rhythm(int argc, char *argv[])" too, with common meaning for those parameters (non-C coders will have trouble with the Virtual Drum Machine).
You can change the tempo (ex. "tempo=100;") or the volume (ex "vol=0.4;") at any time. Each sample comes with its own volume and panning (ex. "a.vol = 0.1;" "a.pan=-0.8;"). Volumes range from 0 to what you want. 1 is for the normal volume. Panning ranges from -1 (left) to 1 (right). 0 is center. All values are double. You can use "volume" instead of "vol", and "panning" instead of "pan". There is no global panning, if you want all left, set all samples to left.
To run in stereo mode, dont forget "-s" when running the generated program. It is mono by default.
You absolutely need to compile and run the examples, and read them to get the point out of it!
The "rc.conf" file contains configuration informations. You specify the sample by "sample" followed by its name (the one you will use in your rhythm files), then the file that will be played. The name of the sample must start by a letter, followed by letters and/or numbers (it must be a valid C identifier, without "_" though). The configuration file contains the install directory, used by "rc" to compile your rhythms. Take a look at the one that is provided to see how to use it.
The sound files are simple wav files. They all should be of the same rate, which can be specified to the generated program, using the "-f" option (44100 is the default). (The library only handles very basic wav files, if yours dont work, you probably will have to modify the library for the program to handle it.)
When you add a sample, you must modify "rc.conf" for the changes to appear. The samples are hard-linked to the produced program, so if you change "sample a /some/dir/file1.wav" by "sample a /one/other/dir/file2.wav" in the configuration file, the previously generated programs will still use "/some/dir/file1.wav". You will have to compile them again to take the changes into account.
Enhancements:
- The code has been modified to let gcc 4 compile it.

virtualDesktopTools is a set of tools for handling X Window virtual desktops.

It makes it possible to switch the virtual desktop to the one indexed by a command line argument, and displays the number of desktops and index of the currently selected one.

It should work with all EWMH-compliant window managers.

Virtual server monitor (vsmon) is a monitoring tool for Linux-VServer that gives a system administrator a global view of all vservers running on his park.
For now, it does not offer control over the vservers life cycle (e.g. provisioning, start, stop, and restart operations). To use vsmon, you must deploy one backend on each vserver host and one frontend, preferably in its own vserver.
Enhancements:
- The frontend was reworked to display a summary of all hosts.
- An owner can be assigned to each vserver.
- The backend can be used on hosts without Linux-VServers, and it no longer obtains IP addresses.
- The libdnet dependency was removed.
- The parsing of /proc/"pid"/stat now works for kernel 2.6.18.
- A Nagios plugin was added, which enables the use of the vsmon backend to monitor a host disk, memory, and swap.
- The plugin monitors all mount points according to an "intelligent" algorithm, which determines warning and critical thresolds as a function of the total size of the partition.

The Virtual Data Center (VDC) is a digital library system "in a box" for numeric data.

The VDC is a web application which provides everything necessary to maintain and disseminate collections of research studies: including facilities for the storage, archiving, cataloging, translation, and dissemination of each collection.

It includes on-line analysis, powered by the R Statistical environment. It also provides extensive support for distributed and federated collections including: location-independent naming of objects, distributed authentication and access control, federated metadata harvesting, remote repository caching, and distributed virtual

The "Virtual Universe" is a 3D cyberspace which offers more possibilities than just chat: it is a combination of the Web, chat, and instant messaging within a realistic, three-dimensional cyberspace.
The "Virtual Universe" is a virtual reality environment which runs on top of the Internet.
Main features:
- chat with each other
- see the chat-partner as a virtual, three-dimensional person
- interact and communicate
- be creative in many ways
- create own worlds for any desired subject
Enhancements:
- A lighting bug in .COB/.SCN loader has been fixed.