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Posts Tagged ‘c shell’

BD-shell 1.0.0 RC2 is out! Processes in background are dangerous

September 13th, 2008 bodom_lx No comments

Release Candidate 2 for my C shell is out. This is a real release candidate, code is frozen and hopefully this one does not have serious bugs like RC1. As you may know, RC1 has been retired because of a bug causing a segmentation fault when launching short commands in background. Let’s see why this happened. The following schema summarizes what happens when a program in background is launched:

Schema for BD-shell, anatomy of process handling

Schema for BD-shell, anatomy of process handling


As you see, there is a non-synchronous function that is called when the child exits, the SIGCHLD handler.
What if the background command is very short, like ls? It may happen that SIGCHLD is thrown before the job object creation. Bdsh RC1 did not manage this case, and crashed. RC2 fixes this and does not have relevant bugs according to my definition of 1.0.0 release.

Finally, go and grab the code!

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Projects

January 24th, 2008 bodom_lx No comments

Pomodroid
A Java/Android application that interacts with a Trac
system, retrieves developer’s tasks and lets him work following the basic rules of the Pomodoro technique.

Pomotux
A task manager implementing the Pomodoro Technique

BD-review
A dynamic website to allow people to review releases (albums, demos, EPs, singles) of (young, unsigned) music bands. Written using a small subset of JavaEE technologies, without the use of web-frameworks.

BD-incollo
A dpaste/pastebin clone written using Django

BD-shell
A tiny C shell for Unix systems

BD-theme Zen
BD-blog minimalistic Wordress theme, available for free

BD-theme
Old BD-blog Wordress theme, available for free

Unipoli
A well-written Java implementation of the popular Monopoli game by Hasbro. It is a project I wrote with other 3 University mates following a software development cycle (Scrum). Unipoli was the project for our Programming Project course. Source code included, released under GPL. We also provide Javadoc, user stories, uml diagrams, binaries.

Computer Shop Warehouse IDA
A very simple, not really useful IDA (Individual Database Application) developed for the “Introduction to Database Systems” course. The documentation is really interesting


Do you think my projects are useful? Has one of my projects helped you at the University? Do you like to learn something from my experience? Are you happy to be able to download every source code?
Then, why don’t you consider a small donation? Donations are useful to maintain my domains and the infrastructures that host my Projects. I’m just a student, I’m not interested to earn profits from my projects, that will always remain free. But I would be delighted to don’t pay for them :-)

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