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Script arguments are passed as
$0(name of the script),
$1(first argument) etc.
$*- all arguments, as single word.
$@ - all arguments, but each is seen as a separate word
Check if a given argument was provided
if [ ! -n "$1" ] then echo "First argument not given" fi
Handling errors from launched programs.
Exit code from last executed command is in
if [ "$?" -ne "0" ]; then echo "last command failed" exit 1 fi