Insider Tips: Locks
Competitive Thinking
A genuine multitasking system like Linux runs many processes concurrently. Programs must compete for data access. Assigning locks to files ensures exclusive access and prevents the possibility of data.
Most Linux machines have an MTA, a Mail Transfer Agent. This can be Postfix, Exim or even Sendmail. The MTA either uses a Fetchmail process or TCP to fetch email messages. When the MTA finds a message addressed to the local user, it passes the message on to the Local Delivery Agent (LDA). And the LDA stores the message in a mailbox file, after possibly taking a detour via a filter such as Procmail. If two messages arrive at the same time, the MTA will hand both of them to an LDA process at the same (see Figure 1). Each process will then attempt to write to the same mailbox file, again at the same time. If you are lucky, the messages end up in the right file, but in the wrong order, but you are far more likely to lose a file as the processes overwrite each other’s data.
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
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
-
Gnome’s Dash to Panel Extension Gets a Massive Update
If you're a fan of the Gnome Dash to Panel extension, you'll be thrilled to hear that a new version has been released with a dock mode.
-
Blender App Makes it to the Big Screen
The animated film "Flow" won the Oscar for Best Animated Feature at the 97th Academy Awards held on March 2, 2025 and Blender was a part of it.
-
Linux Mint Retools the Cinnamon App Launcher
The developers of Linux Mint are working on an improved Cinnamon App Launcher with a better, more accessible UI.
-
New Linux Tool for Security Issues
Seal Security is launching a new solution to automate fixing Linux vulnerabilities.
-
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.