The option is ignored on Windows, and GUC data_directory_mode already
mentioned that within its description in the documentation.
Author: Michael Paquier
Reported-by: Haribabu Kommi, David Steele
Discussion: https://postgr.es/m/CAJrrPGefxTG43yk6BrOC7ZcMnCTccG9+inCSncvyys_t8Ev9cQ@mail.gmail.com
Back-through: 11
<listitem>
<para>
Allows users in the same group as the cluster owner to read all cluster
- files created by <command>initdb</command>.
+ files created by <command>initdb</command>. This option is ignored
+ on <productname>Windows</productname> as it does not support
+ <acronym>POSIX</acronym>-style group permissions.
</para>
</listitem>
</varlistentry>