For consistency with the rest of the docs.
Michael Paquier
<para>
All of these functions take an optional <parameter>missing_ok</> parameter,
- which specifies the behaviour when the file or directory does not exist.
+ which specifies the behavior when the file or directory does not exist.
If <literal>true</literal>, the function returns NULL (except
<function>pg_ls_dir</>, which returns an empty result set). If
<literal>false</>, an error is raised. The default is <literal>false</>.