Bash magic

bash.md

Argument

echo $1 $2  # argument by position
echo $@  # all arguments

Default

echo ${x:-default value}  # equiv to python: "x or 'default value'"

Substring

echo ${parameter:offset:length}

Don't stop and also save exit status

set -e
EXIT_CODE=0
command || EXIT_CODE=$?
echo $EXIT_CODE