To convert string to integer:
NUM="99" NUM=$(($NUM+0))
To set environment variables
export VARIABLE=something/etc/environment - Use this file to set up system-wide environment variables.
/etc/profile – Variables set in this file are loaded whenever a bash login shell is entered.
Per-user shell specific configuration files. For example, if you are using Bash, you can declare the variables in the ~/.bashrc
Per-user shell specific configuration files. For example, if you are using Bash, you can declare the variables in the ~/.bashrc:
source ~/.bashrc