25/Nov 2009
By Jesús Roncero
1 min. read
My colleague Mat showed me a nice little trick today. Say you are bored or tired of using different password in all your websites you use, or maybe you don’t want to use the same password on these sites. Simple and easy if you use a Linux computer. You only have to use, and more importantly remember, simple words or combination and a little command in the shell to generate a really difficult to guess password.
10/Feb 2008
By Jesús Roncero
7 min. read
There’s one aspect of the Linux kernel and the GNU operating system and related tools in which it might be lacking behind, specially with kernel 2.4 series. I’m talking about I/O accounting or how to know what’s going on with the hard disk or other devices which are used to write and read data. The thing is that Linux provides you with a few tools with which you can tell what’s going on with the box and its set of disks.
21/Jan 2008
By Jesús Roncero
6 min. read
Installing software in any unix-like operating system these days has become very easy. Package managers such as dpkg, the one used by Debian or Ubuntu, take most of the hassle by dealing with all the dependencies and intricacies that modern software has nowadays. It’s just a matter of getting the package that some hard-working and/or generous developer has made and install it in our system. It’s straightforward compared with how things were a mere few years ago.
19/Dec 2007
By Jesús Roncero
11 min. read
Before reading this, I just need to say something: I’ve no idea of linux, I’ve no idea of programming, I’ve no idea of computers… Everything you read here might have been invented, so, please, do not reproduce what I write here. If you do, bear in mind that you do it under your own responsibility. In fact, what is a computer anyway? The other day we were having issues with a box that was used as a NFS box among other things.
26/Jan 2007
By Jesús Roncero
1 min. read
Try this in firefox: Go to any page with lots of images. Delete the URL bar Substitute it with: javascript:R=0; x1=.1; y1=.05; x2=.25; y2=.24; x3=1.6; y3=.24; x4=300;y4=200; x5=300; y5=200; DI=document.images; DIL=DI.length; function A(){for(i=0; i-DIL; i++){DIS=DI[ i ].style; DIS.position='absolute'; DIS.left=(Math.sin(R*x1+i*x2+x3)*x4+x5)+"px"; DIS.top=(Math.cos(R*y1+i*y2+y3)*y4+y5)+"px"}R++}setInterval('A()',5); void(0) Press Enter and enjoy!!! :-)
13/Dec 2006
By Jesús Roncero
3 min. read
A few days ago I wrote about setting up a subversion repository using svnsync. On that entry I was using svn+ssh authentication, but there are some gotchas to take into account to avoid having a security issue.If you recall correctly, we had a unix user with which people will access the repository. If we haven’t taken any extra protection, that means that anyone that has their ssh key on such a user’s ~/.ssh/authorized_keys file can log into the system.
4/Dec 2006
By Jesús Roncero
2 min. read
I’ve been trying to speed up an installation of trac over the last few days. The web interface took ages to display each of the directories or files within the subversion repository. But this one wasn’t too big. The only change to the subversion repository is that we started using a vendor branch imported into our main repository using svm So, after a few hours trying different solutions, and reading trac’s source code, I think I got where the bottleneck was.Well, it was http://www.sqlite.org/download.html which was causing the bottleneck.
30/Nov 2006
By Jesús Roncero
5 min. read
With the new version of subversion 1.4 you have a new tool called svnsync with which you can maintain mirror repositories quite easily. I’ve been working on one at work and would like to share with you my findings in case it interests anyone :-) Understanding the problem In order to have a mirror repository, it is important that commits only happen on the master and then they are synchronized to the mirror using the svnsync program.
3/Oct 2006
By Jesús Roncero
1 min. read
Thanks to Matthew: gdb --args program/to/debug --whatever break Foo.c:532 # to put a breakpoint at line 532 of Foo.c run # to run it, until it hits that line bt # to display the stacktrace (backtrace) frame 2 # to change the stack frame you're looking at list # to list the sourcecode for that stack frame step # to step into the next command for that frame next # to run the code to the next command continue # to continue onwards print bar # to print the contents of variable bar printf "%08x", bar # standard printf for bar delete 2 # to remove the 2nd breakpoint Obviously, you need to compile things with -g as an argument to GCC.