When you need to sign a PDF document, it's quite easy to do in Libreoffice Draw for instance. You can just insert an image of your signature and print to PDF afterwards. Sometimes LibreOffice will not do a great job with opening some types of PDF documents. In these cases you can try to use "Lumin PDF" which can be accessed directly from Google Drive when you open a PDF document. You will be asked to accept the Lumin PDF connection to your Google account. You will need to accept the conditions and you are ready to go.
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Replace cartridge: Open access to printer, press stop 5 seconds and repeat. You don't need to replace the cartridge, you can clean it carefully with some soft tissue.
Youtube: How to remove the print head
Rename wordpress database prefix (https://iandunn.name/2016/07/21/rename-wordpress-database-prefix-with-w…)
Change site URL:
wp search-replace 'example.dev' 'example.com' --skip-columns=guid
Or, if you only want to change the option, you can do:
wp option update home 'http://example.com'
wp option update siteurl 'http://example.com'
<?php
define('DISALLOW_FILE_EDIT', true);
echo "\n DISALLOW_FILE_EDIT is: " . constant('DISALLOW_FILE_EDIT') . "\n";
//$constants = get_defined_constants();
//var_dump($constants); // pretty large list
?>
Key words: define defined constant constants
To detach a process started in the terminal, you can always add & at the end. For example: npm run evaluation &
Or: nohup bash script.bash &
After that you can run "jobs", to see the running jobs for that user.
Otherwise you can use "htop" or "ps -ef |grep bash" to find all bash jobs for instance.
References:
https://www.dev2qa.com/how-to-run-node-js-server-in-background/
Check if file or directory exists, multiple ways: https://linuxize.com/post/bash-check-if-file-exists/
You can see a lot of good information for debugging and fixing errors on your Ubuntu server with journalctl and dmesg
journalctl --since "1 days ago"
journalctl --since "10 hours ago"
journalctl --since "12 hours ago" -p 3 -x --utc --no-pager
dmesg | less
dmesg -H --time-format iso| less
Resources:
https://unix.stackexchange.com/questions/50098/linux-network-troublesho…
Wordpress runs it's cron job automatically approximately every 10 minutes. Sometimes it is blocked by .htaccess or other server configuration. To avoid issues, it might be a good idea to run from the server crontab itself.
References:
https://kinsta.com/knowledgebase/disable-wp-cron/
https://wpbeaches.com/set-up-wordpress-wp-cron-php-to-run-manually/
find [FOLDER_NAME]/* -prune -mtime +14 -exec rm {} \;
This is the best option I have found so far: find . -type f -exec sed -i 's/foo/bar/g' {} +
foo is replaced with bar.
Source: https://linuxize.com/post/how-to-use-sed-to-find-and-replace-string-in-…
Also quite handy to be able to search and replace filenames.
Example bash on argument 1. It checks if HTTPS is up and if the domain-name is on the site. Most sites have the domain name on the front page somewhere: /usr/local/nagios/libexec/check_http -H $1 --ssl --onredirect=follow --string "$1"
If log file you can run grep on the following keywords: grep -i -e "critical" -e "invalid" -e "warning" [LOGFILE.log]
Keywords: check_http
If you have the black screen of death when trying to get back from suspend mode, you might want to check out this bug description and possible resolutions: https://bugs.launchpad.net/ubuntu/+source/plasma-desktop/+bug/1849084
Otherwise disable compositor: qdbus org.kde.KWin /Compositor suspend
Check if compositor is enabled: qdbus org.kde.KWin /Compositor org.kde.kwin.Compositing.active
Or: qdbus org.kde.KWin /KWin supportInformation
sudo systemctl stop apport
sudo systemctl stop whoopsie
sudo systemctl disable apport
sudo systemctl disable whoopsie
sudo aptitude purge apport whoopsie
Source: https://askubuntu.com/questions/1245078/woopsie-upload-all-process-cons…
A nice little guide: https://tecadmin.net/run-shell-script-as-systemd-service/
In firefox I have enabled a couple of tweaks described here for hardware acceleration: https://askubuntu.com/questions/1216192/why-is-kubuntu-using-much-more-…
Maybe more info here: https://itectec.com/ubuntu/ubuntu-why-is-kubuntu-using-much-more-cpu-th…
If you experience false characters in your mysqldump, you might want to try to set the encoding specifically. Example with latin1:
mysqldump -u [USER] -p --opt --skip-set-charset --default-character-set=latin1 [DATABASE_NAME] > [OUTPUT_FILE_NAME].sql
Check different encoding settings in mysql when using a specific database: show variables like 'char%';
More info and tips: https://www.toptal.com/php/a-utf-8-primer-for-php-and-mysql
Use "xdotool key Menu" in a global shortcut. That's it!
Currently running flutter in ubuntu 20.04.
Flutter cli doc: https://flutter.dev/docs/reference/flutter-cli
Flutter pub doc: https://dart.dev/tools/pub/cmd
KVM installation: sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients bridge-utils virtinst virt-manager
Old info: sudo apt install qemu qemu-kvm virt-manager (Remember to enable VT Virtualization in the Bios) - run: sudo kvm-ok (to check)
If you encounter this problem when reading csv-files, you might want to try to change the encoding from UTF-8 to latin1. This worked for me when using the tolower function in R.
Pretty nice solution here with gsub (https://stackoverflow.com/questions/38828620/how-to-remove-strange-char…):
The text editor "nano" is an easy to use editor for linux etc.
Here are som great options to add:
File: ~/.nanorc
Content:
set linenumbers
set softwrap
set tabsize 4