(This is a variant of the standard LDP disclaimer.)
No liability for the contents of this document can be accepted. Use the concepts, examples and information at your own risk. There may be errors, omissions, and inaccuracies that could cause you to lose data or harm your system, so proceed with appropriate caution. The author takes no responsibility for any damages, incidental or otherwise.
As it happens, it is highly unlikely that either you or your system will suffer ill effects. In fact, the raison d'etre of this book is to enable its readers to analyze shell scripts and determine whether they have unanticipated consequences.