TOPIC: REQUEST TRACKER
Installing Perl modules using CPAN on Linux Mint 19.2
28th September 2019My online travel photo gallery is a self-coded set of PHP scripts that read data from tables in a MySQL database. These tables are built from input XML files using a Perl script that itself creates and executes an SQL script. The Perl script also does some image processing using GraphicsMagick commands to resize images and to add copyright information and image framing. Because this processed one image at a time sequentially, it was taking several minutes to complete and only partly used the capacity of the PC that I used.
This led me to look at adding parallel processing, which is what brought me to looking at the Parallel::ForkManager Perl module. An alternative approach might have been to add new images in such a way as not to need the full run involving hundreds of image files, but that will take more work and I fancied having a look at parallelising things anyway.
If it was not there already, the first act would have been to install build-essential to get access to the cpan command. The following command accomplishes this:
sudo apt-get install build-essential
Once that is there, the cpan command needs to be run and some questions answered to get things going. The first question to answer is whether you want setup to be as automated as possible, and the default answer of yes worked for me. The next question to answer regards the approach that cpan takes when installing modules: I chose sudo here (local::lib is the default value and manual is another option). After this, cpan drops into its own command shell. Here, I issued two more commands to continue the basic setup by updating CPAN.pm to the latest version and adding Bundle::CPAN to optimise the module further:
make install
install Bundle::CPAN
Continuing the last of these may need extra intervention to confirmation the suggested default of exit at one point in its operation, which takes a little time to complete. It is after this that Parallel::ForkManager can be installed using the following command:
install Parallel::ForkManager
That completed quickly and the cpan shell was exited using its exit command. Then, the new module was available in scripting after that. The actual use of this module is something that hope to describe in another post, so I am ending this one here, and the same process is just as applicable to setting up cpan and adding any other Perl CPAN module.
Ubuntu 9.04 and Tracker
30th April 2009Shortly after it was released, I did the upgrade shuffle very painlessly, and it didn't take up so much time either. There was only one issue: Tracker falling over, complaining about corrupted indices. That got it removed from my system using apt-get remove (apt-get purge is another option, especially if you need to rid yourself of nefarious configuration files). After having a bit of a dig around the web, I found that I wasn't the only one seeing the problem. To me, it looks as if the upgrade to 9.04 doesn't work so well when it comes to Tracker, and it needs to be removed and reinstalled to ensure that all required dependencies are correctly set in place. Since I restored it on my system, all is working without complaint. Other than the Tracker issue, it has been a case of another uneventful upgrade. Though the evolutionary path that Ubuntu is following may disappoint anyone looking for excitement, no one would upgrade every six months if they knew that disruptive damage or upheaval might be caused. While I may do a clean installation at some point, that is well down the priority list right now.