bash
Cleanup a script on exit using trap
Environment variable defaults
Default and alternative command
Provide an alternative command if the preferred command is not available.
Elevate script to sudo
Parallel
Run commands in parallel
Add directory to $PATH if it doesn't exist
Check if a variable is set
Check network connectivity
Check if a file ends with newline
Log script output to file and console
Safe Scripts (Strict Mode)
Script dir and path
Get the directory and path of a script.