https://heyn.dev/ Recent content on heyn.dev Hugo -- gohugo.io en-us Fri, 22 Mar 2024 00:02:18 +0000 https://heyn.dev/posts/integration-of-a-local-cloudflare-domain-update-service-for-use-with-fritzbox-dyndns-feature/ Fri, 22 Mar 2024 00:02:18 +0000 https://heyn.dev/posts/integration-of-a-local-cloudflare-domain-update-service-for-use-with-fritzbox-dyndns-feature/ This is a follow-up of the How-to-use-Fritz!Box-DynDNS-feature-with-cloudflare guide. As you may have noticed, the solution described in the old guide no longer works with newer versions of Fritz!OS. This is because the Fritz!Box doesn’t allow http DynDNS updates anymore, even if they point to local IPs. This guide will provide an updated solution and clean up the old solution using docker compose. Understanding certificates and challenges Digital certificates and CAs A digital certificate is a file hosted on a server to enable encryption. https://heyn.dev/posts/face-detect-align-crop-an-app-that-creates-uniform-looking-id-portraits-from-very-heterogeneous-pictures/ Thu, 04 Jan 2024 00:52:24 +0000 https://heyn.dev/posts/face-detect-align-crop-an-app-that-creates-uniform-looking-id-portraits-from-very-heterogeneous-pictures/ My university has a strong student community. Large events are held on a regular basis. To keep costs down, many students volunteer to help with various tasks, such as cooking or selling food and drinks. This requires a certain amount of coordination and sometimes strict separation from the guests. Portrait ID cards are used for this purpose. To produce these, a photo of each volunteer is required. However, the photos vary in size, quality and orientation. https://heyn.dev/posts/how-to-use-fritzbox-dyndns-feature-with-cloudflare/ Fri, 29 Dec 2023 00:58:23 +0000 https://heyn.dev/posts/how-to-use-fritzbox-dyndns-feature-with-cloudflare/ In the age of cloud storage services like Google Drive and Dropbox, it has become easier than ever to store data online. However, the convenience of these tools comes at a significant cost: your privacy. Despite frequent reports of data breaches, corporate and government surveillance, and other privacy violations, many people still use these services not because they agree to it, but because setting up their own servers is an incredibly challenging. https://heyn.dev/posts/reflection-in-c++/ Thu, 22 Sep 2022 00:02:18 +0000 https://heyn.dev/posts/reflection-in-c++/ Reflection means in the context of programming that a program knows its own structure and/or can change it. Reflection allows for example in object-oriented programming the query of information at runtime about the classes. In the case of a class, this includes the name of the class, the defined fields and methods. C++ has no such features. But there are libraries that can emulate such behavior with some tricks. I will briefly present some libraries that I used in the past: https://heyn.dev/posts/raii-abused-using-the-programming-idiom-with-arduino-interrupts/ Wed, 17 Aug 2022 00:00:19 +0000 https://heyn.dev/posts/raii-abused-using-the-programming-idiom-with-arduino-interrupts/ What is RAII? Resource acquisition is initialization abbreviated RAII denotes a programming idiom for managing resources. Here, the allocation of resources is tied to the constructor call of the class and the release of resources is tied to its destructor call, which ensures that they are actually released. The automatic release is triggered by leaving the scope at the end of the block or when an exception is thrown by returning to the caller. https://heyn.dev/posts/exclude-directories-from-search-in-linux/ Thu, 20 Jan 2022 07:57:53 +0000 https://heyn.dev/posts/exclude-directories-from-search-in-linux/ We’re all familiar with the scenario, one makes a mistake with the path input and already the file is lost in the file system. Now you want to find the lost file again… find / -name lost_file Now, however, like me, you have a server with 12 TB of attached ZFS storage and you don’t want the find command to search it as well. You can do this as follows: https://heyn.dev/posts/hello-world/ Thu, 01 Jan 1970 00:00:00 +0000 https://heyn.dev/posts/hello-world/ Welcome to my developer blog.