shadow/man/login.defs.d/UMASK.xml

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   SPDX-FileCopyrightText: 1991 - 1993, Julianne Frances Haugh
   SPDX-FileCopyrightText: 1991 - 1993, Chip Rosenthal
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<varlistentry>
  <term><option>UMASK</option> (number)</term>
  <listitem>
    <para>
      The file mode creation mask is initialized to this value. If not
      specified, the mask will be initialized to 022.
    </para>
    <para>
      <command>useradd</command> and <command>newusers</command> use this
      mask to set the mode of the home directory they create if
      <option>HOME_MODE</option> is not set.
    </para>
    <para condition="no_pam">
      It is also used by <command>login</command> to define users' initial
      umask.  Note that this mask can be overridden by the user's GECOS
      line (if <option>QUOTAS_ENAB</option> is set) or by the
      specification of a limit with the <emphasis>K</emphasis> identifier
      in <citerefentry><refentrytitle>limits</refentrytitle>
      <manvolnum>5</manvolnum></citerefentry>.
    </para>
    <para condition="pam">
      It is also used by <command>pam_umask</command> as the default umask
      value.
    </para>
  </listitem>
</varlistentry>