Unix FIFO File on openhabian - Specifically ZRAM

Hardware Server
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openHAB 5.0.2

Openhabian on RPI 5 8GB Ram

I have a requirement to run a fifo file for some Interprocess communication and would like two bits of device

  1. Any restrictions on openhabian OS on FIFO files and where they should be placed (/tmp is not a great place because of the privacy of /tmp)
  2. Can the FIFO file be created on zram specifically I was thinking in /var/log/openhab even though its not a log file but specifically I do not need to be worried about the content of the FIFO file being lost in this case but at least this folder is know to be on zram

Any advice on this would be great - thanks

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  1. For the most part openHABian is mostly stock Debian/Raspberry Pi OS. There shouldn’t be anything done by openHABian that would impact this.

  2. Try it and find out. I don’t know the underlying mechanisms in play but I would expect it to work in zram.

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Thanks @rlkoshak

A little extra background - I actually did and the last action i did before i had a catastrophic SDCard failure was put the background process in place with the FIFO file in /various/lib/openhab/ipc and between 30 mins to 2 hours later the system died

I had backups AND SD Card Syncs of the system so recovery was good BUT this nagging doubt about why made me ask the question -

There is not a lot of data going to/from the fifo file - in fact only maybe 4-5 times a day if that and a single word

Maybe it was just the coincidence

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If it’s really only writing that little it was almost certainly a coincidence. If it was writing to a tempfs or zram file system it was completely unrelated to the writes as in those cases it’s not even touching the SD card.