Fuzzy_()ctal

I recently got my first raspberry pi, it is being used to run a simple display board at work. Newsletters and announcements are converted to image form and then displayed in a slideshow. After some trial and error I came upon the fbi command, which displays images on a screen directly, no need for an X-session. This has worked really well, I have a script that displays all the .png files in a directory:

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#!/bin/bash
SLIDESHOWDIR="/home/me/slideshow"
INTERVAL=25 # slideshow interval in seconds
fbi -a -t $INTERVAL -u `find $PHOTODIR -iname "*.png"`

A little explanation:

• -a enables autozoom, fbi picks a reasonable zoom factor when loading a new image
• -t $INTERVAL sets the slideshow interval
• -u randomizes the order of the filenames
• find $PHOTODIR -iname "*.png" is encased in backticks¹, so it is run before fbi and the output is used by fbi. In this case we are simply finding all the .png files in the slideshow directory.

The problem arises when I add or remove a file from the slideshow directory via ssh. I don’t want to have to physically plug in a keyboard to my RPi everytime I want to restart the slideshow, but I couldn’t seem to get it to work any other way. This is where the openvt command comes in

$ sudo openvt -f -c 1 ./slideshow.sh

openvt runs a command on a new virtual terminal (VT):

• -f forces the opening of a virtual terminal without checking if it is already in use
• -c specifies the virtual terminal to use (1 in this case)
• ./slideshow.sh is my fbi script from above.

Now changing the slideshow is as simple as ssh-ing in, changing the pictures in the slideshow directory, and running the above command (stashed in a restart_slideshow.sh file)