IT

Disable annoying XFCE automatic maximise window feature

In XFCE when you move a window around and it gets close to the top edge of the screen it suddenly jumps to maximised size – this is never what I want and so I find this feature really annoying.

The setting where this feature can be turned off is hidden in a somewhat counter intuitive location:

Yes, the setting is called ‘Accessibility – Automatically tile …’!

Fix for packet loss and latency problems with Virgin Media cable connections

About ten days ago my network connection with Virgin Media started to play up. I was experiencing significant packet loss, at times in excess of 50%, and increased latency times with peaks at more than 100ms.

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Recovery of scanned PDF corrupted by email transfer

Occasionally when my scanner is emailing me a PDF it gets corrupted along the way. Most of the time the individual scanned images in the PDF are either perfectly valid or at least can viewed, even though the PDF viewer refuses to open the corrupt PDF file.

The bash script below will extract the images and then combine them again into a valid new PDF file.

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Certwatch SSL certificate expiry warning

If you have just received an e-mail similar to the one below, read on.

From: root@your.domain.org To: sysadmin@your.domain.org Subject: The certificate for server.your.domain.org will expire in 13 days Date: yesterday (BST) ################# SSL Certificate Warning ################ Certificate for hostname ‘sws.hlan.laczik.org’, in file (or by nickname): /etc/pki/tls/certs/localhost.crt The certificate needs to be renewed; this can be done using the ‘genkey’ program. Browsers will not be able to correctly connect to this web site using SSL until the certificate is renewed. ########################################################## Generated by certwatch(1)
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Special character mangling in WordPress and SyntaxHighlighter

The SyntaxHighlighter WordPress plug-in is used to display code ‘as is’; unfortunately WordPress again is too clever for its own good and mangles special characters like & and ” even before the text gets to the SyntaxHighlighter blocks in the Block Editor.

The solution is to add a filter function in your custom functions.php file:

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Touchscreen calibration

I found that I use my laptop’s touch screen more frequently – it is particularly useful for image editing. However, when I work in my (home) office I also use a multi-screen set-up with three monitors. The problem is that the touch region of the laptop screen automatically gets scaled to the overall size of my screen, which spans multiple monitors.

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Send message to user logged in to an X11 session at a remote host

There are occasions when you want to contact a user working at a remote computer, but his/her phone is switched off. If the remote user is running an X11 session, and you have ssh access to the remote computer, and you have root privileges on the remote computer, here is a solution.

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Turn your desktop computer into a wireless access point

My desktop computer has a wired connection to the internet and so the built-in wifi card is normally not used. I decided to enable and use it as a wireless access point.

Unfortunately NetworkManager will only create an ad-hoc wifi network, and Android devices will only connect to infrastructure access points. Don’t ask why… A rooted Android phone or tablet can be configured to connect to an ad-hoc network, and if a separate program can configure a Linux box to act as an access point, NetworkManager should be able to do the same. As far as I can see, there are no good technical reasons for either of these deficiencies.

The solution is hostapd:

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