gnowsys-mode
Pencils down declared for GSoC 2009 and here I am to pen down my thoughts/experience. At the start of the project I had visualized it something different but at the end it turned up as much better an application. All thanks to Nagarjuna sir & his great ideas. Since beginning he has been inspiring me to use org-mode features & seriously at the end I feel its the beauty of org-mode that makes gnowsys-mode so simple and yet so pretty.
“gnowsys-mode” is an extension package for Emacs, a text editor. Motivation of the project is collaborative knowledge networking & organization. As a major-mode for Emacs, it dispels the common axiom, that collaborative authoring can be done only through web applications but not from a text editor.
This dialect of knowledge networking offers a prospect of robustness to the shared data, applying GNOWSYS rules of inferences to it. It provides a plethora which lets you semantically conceptualize information/knowledge with the ease of a traditional text editor. Peers using gnowsys-mode may agree on a shared conceptualization of a knowledge domain in the form of ontology, and collectively maintain it over time. Versioning feature of GNOWSYS allows change tracking by creating snapshots & maintaining metadata details of each snapshot.
Adhering to the concepts of semantic web, GNOWSYS allows to convert the knowledge node in RDF tripples. So any knowledge node being created or viewed in gnowsys-mode can also be viewed in respective RDF N3 format. It also enables to visualize the knowledge networks graphically, in the form of concept map.
It is implemented on top of Org mode, which helps to give a formal structure to knowledge network in the form of drawers and also makes it possible to navigate through the network in the text buffer using the node links.
Though Emacs is well known as an editor, gnowsys-mode doesn’t restrict you to work on your desktop but also gives you the freedom to work on a remote GNOWSYS server. We have hosted a server http://sandboxat.gnowledge.org , which is default URL prompted to establish connection with. This is created for the testing purpose, so feel free to connect to it and work around. Or install GNOWSYS on your machine using installer provided here.
To get a live demo on how to use gnowsys-mode, watch the videos provided here.
Get gnowsys-mode from svn repository using:
svn co svn://svn.sv.gnu.org/gnowsys/gnowsys-modesentinel
Finally got the sentinels in the gnowsys-mode 
Nagarjuna sir have been regularly reporting the error time to time. And this was third time he reported the same error:
if: Error during request: 401
error in process sentinel: url-http-async-sentinel: Symbol’s value as
variable is void: url-http-attempt-keepalives
After few google searches I got the solution, it was some sentinel variables which were used by the xml-rpc were not accessible. Thsee variales are part of url-http.el file, so just including it in gnowsys.el solves my problem. Ah! such a problem & one liner solution. Thats the best thing which have been happening to me through out this project, I always get stuck up somewhere & problem appears so big to me unless I get the solution. And funny thing solution is always one liner & so pretty
