$ \textbf{hg init hook-test}
$ \textbf{cd hook-test}
$ \textbf{echo '[hooks]' >> .hg/hgrc}
$ \textbf{echo 'commit = echo committed $HG_NODE' >> .hg/hgrc}
$ \textbf{cat .hg/hgrc}
[hooks]
commit = echo committed $HG_NODE
$ \textbf{echo a > a}
$ \textbf{hg add a}
$ \textbf{hg commit -m 'testing commit hook'}
committed