Sending data in a signal

The well-known kill system call has been around for decades and is used to send a signal to another process. The most common use is to terminate or kill another process by sending the KILL or TERM signal but it can be used for a form of IPC, usually around giving the other process a “kick” to do something.

One thing that isn’t as well known is besides sending a signal to a process, you can send some data to it. This can either be an integer or a pointer and uses similar semantics to the known kill and signal handler. I came across this when there was a merge request for procps. The main changes are using sigqueue instead of kill in the sender and using a signal action not a signal handler in the receiver.

procps-ng 3.3.16

procps-ng version 3.3.16 was released today. Besides some documentation and library updates, there were a few incremental changes. Zombie Hunting with pgrep Ever wanted to find zombies? Perhaps processes with other states? pgrep has a shiny new runstate flag to help you which will match process against the runstate. I’m curious to see the use-cases

WordPress 5.2.4

Hot on the heels of WordPress version 5.2.3 which fixed a bunch of stuff we have WordPress 5.2.4 with fixes for six security issues. There is a certain trick to matching up what the WordPress Blog thinks has been fixed and the changsets between the old version and the new. The curious thing is there

WordPress 5.1.1

The Debian packages for WordPress version 5.1.1 are being updated as I write this. This is a security fix for WordPress that stops comments causing a cross-site scripting bug. It’s an important one to update. The backports should happen soon so even if you are using Debian stable you’ll be covered.

WordPress 5.0.1

While I missed the WordPress 5.0 release, it was only a few more days before there was a security release out. So WordPress 5.0.1 will be available in Debian soon. This is both a security update from 5.0.1 and a huge feature update from the 4.9.x versions to the 5.0 versions. The WordPress website, in