How Perl programmers efficiently manage asynchronous program flows
Pyramid of Doom
Asynchronous program flow quickly degenerates into unreadable code if it lacks an overarching concept to provide structure. Fortunately, the JavaScript community has invented some functional tricks that also help tame asynchronous Perl code.
Even experts can unintentionally build race conditions into their code. Even they can easily overlook the side effects when multithreading suddenly interrupts the flow of code. Emergency teams later have to discover the causes, which involves a huge amount of effort. After all, the error the customer reports occurs only sporadically, because it only occurs given the temporal coincidence of certain events that cannot be easily reproduced by the development department.
One Thread Is Enough
If only one thread is running – as in a JavaScript application – then there can be no such race conditions, because the CPU runs the code as written, and nothing unexpected interrupts the flow. In other words, this approach has its benefits.
For a program with only one thread to run as fast as one with multiple threads, however, it must not be allowed to sit and twiddle its thumbs while, for example, a much slower network operation is in progress. To allow this to happen, the programmer relinquishes control over selected parts of the program to an event loop, which executes the events asynchronously. Once a programmer's brain has mastered the jump to asynchronous program flows, even complicated processes are wonderfully easy to write. Before that happens, however, some hurdles must be taken.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Ubuntu 25.04 Coming Soon
Ubuntu 25.04 (Plucky Puffin) has been given an April release date with many notable updates.
-
Gnome Developers Consider Dropping RPM Support
In a move that might shock a lot of users, the Gnome development team has proposed the idea of going straight up Flatpak.
-
openSUSE Tumbleweed Ditches AppArmor for SELinux
If you're an openSUSE Tumbleweed user, you can expect a major change to the distribution.
-
Plasma 6.3 Now Available
Plasma desktop v6.3 has a couple of pretty nifty tricks up its sleeve.
-
LibreOffice 25.2 Has Arrived
If you've been hoping for a release that offers more UI customizations, you're in for a treat.
-
TuxCare Has a Big AlmaLinux 9 Announcement in Store
TuxCare announced it has successfully completed a Security Technical Implementation Guide for AlmaLinux OS 9.
-
First Release Candidate for Linux Kernel 6.14 Now Available
Linus Torvalds has officially released the first release candidate for kernel 6.14 and it includes over 500,000 lines of modified code, making for a small release.
-
System76 Refreshes Meerkat Mini PC
If you're looking for a small form factor PC powered by Linux, System76 has exactly what you need in the Meerkat mini PC.
-
Gnome 48 Alpha Ready for Testing
The latest Gnome desktop alpha is now available with plenty of new features and improvements.
-
Wine 10 Includes Plenty to Excite Users
With its latest release, Wine has the usual crop of bug fixes and improvements, along with some exciting new features.