Ssh, linux

Monday, 31 October 2011

Install Latest Versions and New Applications using GetDeb under Ubuntu

GetDeb is an unofficial project with the mission to provide the latest open source and freeware applications for the current Ubuntu Linux release, in an easy to install manner.

The GetDeb repository extends the official repositories by providing latest versions and new applications. Unlike the official packages, GetDeb packages do not have a predefined release schedule - new software versions are provided as they become available from their authors. There is a short and limited testing phase instead of a full testing cycle to ensure packaging quality, however it is less strict than Ubuntu's official requirements.

You may also be interested on the UbuntuBackports project. It has a limited scope compared to GetDeb but the advantage of being an Ubuntu official project.

Visual Real-Time Apache Log Analyzer - GoAccess

20:30 No comments

GoAccess is an open source real-time Apache log analyzer and interactive viewer that runs in a terminal in *nix systems. It provides fast and valuable HTTP statistics for system administrators that require a visual server report on the fly.

Essentially, the way GoAccess works is that it will parse the well-known Apache access log file, from there, GoAccess will collect data from the parsed log and it will display it to the console or the X terminal. The collected information or generated reports will be displayed to the user/sysadmin in a visual/interactive window. Reports include:
* General Statistics, bandwidth etc.
* Top Visitors
* Requested files
* Requested static files, images, swf, js, etc.
* Referrers URLs
* 404 or Not Found
* Operating Systems
* Browsers and Spiders
* Hosts, Reverse DNS, IP Location
* HTTP Status Codes
* Referring Sites
* Keyphrases
* Different Color Schemes
* Unlimited log file size

Multimedia (MP3, MPEG-4, AVI, DiVX, etc.) support in Ubuntu 11.10 (Oneiric Ocelot)

10:19 No comments

Why doesn’t Ubuntu support MP3 ‘out of the box’?

Ubuntu cannot include support for MP3 or DVD video playback or recording. MP3 formats are patented, and the patent holders have not provided the necessary licenses. Ubuntu also excludes other multimedia software due to patent, copyright, or license restrictions, such as Adobe Flash Player and RealNetworks RealPlayer.

That doesn’t mean you can’t play .mp3 files in Ubuntu , it just takes a bit of work (not much).

Follow these instructions to get mp3 and other multimedia support on your Ubuntu 11.10.

Tool for Detecting Memory Management Problems in Programs - Valgrind

21:00 No comments

Valgrind is a powerful tool for detecting memory management problems in programs. The kinds of problems it can detect are often very difficult to find by other means and often cause difficult to diagnose crashes. Valgrind can be used with existing executables without recompiling or relinking, although the output it produces will be much more useful if you have compiled with the -g flag.

Valgrind Capabilities
Valgrind is basically an x86 emulator that checks all reads and writes of memory, intercepts all calls to allocate and deallocate memory. The memcheck tool of valgrind (which is the main tool and the only one covered in this chapter) can detect the following:

* Use of uninitialized memory
* Reading/writing memory after it has been free'd
* Reading/writing off the end of malloc'd blocks
* Reading/writing inappropriate areas below the stack.
* Memory leaks
* Mismatched use of malloc/new/new[] vs free/delete/delete[]
* Overlapping src and dst pointers in memcpy() and related functions
* Doubly freed memory
* Passing unaddressable bytes to a system call