Tiny Tiny RSS / MySQL: Problems with UTF8 Emojis

Since Google shut down its Reader service, I am a regular user of the Tiny Tiny RSS reader. Having my own RSS reader installation gives me more power regarding my privacy and the services I am using. Consider me a happy user.

However, there are some issued regarding full UTF8 support when using MySQL. When a feed uses UTF8 emoijs, tt-rss will throw up and report an error. Unfortunately, this only manifests itself with log entries like this:

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Algorithm to find first available number

So recently I stumbled across a programming quiz to which I later returned because it somehow fascinated me.

Problem

Finding the first available number (or the smallest missing number) in a list is a common problem in Computer Science (for example for Defragmenting or generating keys) and describes the search for the smallest natural number, which is not part of a set X of natural numbers. X is a set of distinct natural numbers (and being a set, is not ordered).

We are now looking for a function with linear worst-case time complexity O(n).

Example

We define X as a set of distinct natural numbers:

X = {23,9,12,0,11,1,13,7,21,14,5,4,17,19,3,6,2}

So in this set, we find that the number 8 is the first available number (smallest missing number). So running the algorithm over the above set should return 8.
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VMWare Server 2.0: SSL Exception: error:00000000:lib(0):func(0):reason(0)

Last week, someone at work approached me, stating that he was unable to log into the web interface of a VMware Server machine. I was shocked to learn that we still had a VMware Server up and running. Then, I tried to log into the web interface myself and received an SSL error as well.

It turns out the machine was standing under someones desk and still had one single VM running. In order to migrate the machine to our ESXi infrastructure and fix the problem, I examined the logs on the server and found this:

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Debian: Script for SFTP users

When using a server with multiple external users, one thing that regularly comes up is that users want to access a folder on the server, such as the root folder for a webserver. This way every user can manage their files and upload new content. This can be achieved securely with SFTP, which uses the SSH protocol for file transfers.

In this article, I provide a simple script to create new users with minimal preparation and all correct settings. The text is based on the following article on debian-administration.org: OpenSSH SFTP chroot() with ChrootDirectory.

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