Basic commands and tools

Merge PDF files

gs -dBATCH -dNOPAUSE -q -sDEVICE=pdfwrite -dAutoRotatePages=/None -sOutputFile=finished.pdf  rg2020.pdf rg2020-ver.pdf 

How to print a total of register from a table? Total COUNT in postgreSQL.

To create a file with the follow content:

echo "SELECT COUNT(*) FROM client_client WHERE confirmed=1;"  > /tmp/command.sql

Print date time and total of occurences 5 to 5 minutes, sleep command work’s in seconds, crtl+c to out. Execute the command as postgres user.

su - postgres 
while [ -z ]; do date && psql -d mydatabase < command.sql; sleep 300; done

The best traffic monitoring

iptraf-ng

My current IP address via line command

curl checkip.amazonaws.com
curl ifconfig.me
curl icanhazip.com
curl ipecho.net/plain
curl ifconfig.co

Show resume of process and use memory for each service

https://github.com/pixelb/ps_mem
git clone https://github.com/pixelb/ps_mem.git