Łukasz Herok

Photomultiplier tubes are extremely sensitive detectors of light

1 photon > cathode> 1 electron >> ... > n*electron >> ... > anode

#physics

Repairing LibrreOffice conversion odt to pdf in parallel PHP script, as it sometimes hangs.

<?
$cmd = 'export HOME=/tmp && cd /tmp  && libreoffice --headless --convert-to pdf  ~/16c6801746f3e924b254abb0089f0a0f.odt ';
exec($cmd, $output, $retCode);

The problem is in access to /tmp/.config and /tmp/.cache for the same user (apache) from different processes. The solution was to generate a temporary subdir for every conversion and pass it to HOME parameter.

#soft

$ podman network create nextcloud-net
$ podman network ls
$ podman network inspect nextcloud-net

$ podman volume create nextcloud-app
$ podman volume ls
$ podman volume inspect nextcloud-app

Installing Nextcloud 20 on Fedora Linux with Podman

Add new disk in OVH public cloud server

Storage > Block Storage > Create new instance

Attach it to the instance using context menu [...]

$ lsblk
$ fdisk /dev/vdb
# n -> default answers , w
$ mkfs.ext4 /dev/vdb1
$ mkdir /mnt/disc1

# fstab
$ blkid
$ vim /etc/fstab
$ mount -a

#$ sudo mount /dev/vdb1 /mnt/bazy

https://docs.ovh.com/pl/public-cloud/utworzenie_i_konfiguracja_dodatkowego_dysku_dla_instancji/ #linux #soft

Podman (docker) cheatsheet

podman logs postgres12

Postgresql from container

$ podman pull postgres
$ mkdir ~/podman/volumes/postgres
$ podman run --rm --name pg-docker -e POSTGRES_PASSWORD=docker  
   -d -p 5432:5432 \r
   -v $HOME/podman/volumes/postgres:/var/lib/postgresql/data:z postgres
$ podman ps
$ psql -h localhost -W -U postgres
$ podman stop pg-docker

The :z suffix solves the permission denied problem for the volume.

#podman #docker

Don't write command-line interfaces (generate them)

Instead of writing a command line menu use hug or typer - it is like implementing REST interface for your command line program.

#python

Setting up a time zone

timedatectl list-timezones | grep Wars
sudo timedatectl set-timezone Europe/Warsaw
timedatectl status

How To Use Journalctl to View and Manipulate Systemd Logs

#linux

Improve the Font Rendering In Firefox

Create a file ~/.fonts.conf and put the contents from: StackExchange

#linux

Journal of my recent activities

Postgresql from container