Error, cannot render titles without an X11 environment

July 27, 2019 - Reading time: ~1 minute

“Error, cannot render titles without an X11 environment”

This is error occurs when try run MLT (melt) without packages:
librsvg2-2, librsvg2-common


Postfix queue

July 27, 2019 - Reading time: ~1 minute

Delete mail from queue:

postsuper -d id

List queue:

postqueue -p

Flush queue:

postqueue -f

Delete msg from MAILER-DAEMON

mailq | grep 'MAILER-DAEMON' | awk '{print $1}' | postsuper -d -

Find IP Addresses with awk

July 26, 2019 - Reading time: ~1 minute
awk '{match($0,/[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+/); ip = substr($0,RSTART,RLENGTH); print ip}'