PAM documentation - Mailing list pgsql-docs

Tom Lane wrote:
> momjian@svr1.postgresql.org (Bruce Momjian) writes:
> > Mention that PAM requires the user already exist in the database, per
> > Dick Davies.
>
> I don't recall exactly what Dick suggested, but the patch as applied
> seems like fairly useless verbiage.  Exactly which of our other auth
> methods allow users who *don't* exist in the database to log in?
> And why would anyone find it surprising that this does not happen?

Can someone comment if having to create the database user account to use
PAM is something that people forget?  Is there increased confusion
because PAM is usually used for the operating system usernames?

Attached is the addition I made to the docs recently.  Is it useful?

Here is the email that prompted the addition:

    http://archives.postgresql.org/pgsql-admin/2005-03/msg00189.php

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
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Index: client-auth.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/client-auth.sgml,v
retrieving revision 1.76
retrieving revision 1.77
diff -c -c -r1.76 -r1.77
*** client-auth.sgml    22 Apr 2005 04:18:58 -0000    1.76
--- client-auth.sgml    26 Apr 2005 03:01:09 -0000    1.77
***************
*** 883,890 ****
      default PAM service name is <literal>postgresql</literal>. You can
      optionally supply your own service name after the <literal>pam</>
      key word in the file <filename>pg_hba.conf</filename>.
!     For more information about PAM, please read the
!     <ulink url="http://www.kernel.org/pub/linux/libs/pam/">
      <productname>Linux-PAM</> Page</ulink>
      and the <ulink url="http://www.sun.com/software/solaris/pam/">
      <systemitem class="osname">Solaris</> PAM Page</ulink>.
--- 883,892 ----
      default PAM service name is <literal>postgresql</literal>. You can
      optionally supply your own service name after the <literal>pam</>
      key word in the file <filename>pg_hba.conf</filename>.
!     PAM is used only to validate username/password pairs.
!     The user must already exist in the database before PAM
!     can be used for authentication.  For more information about
!     PAM, please read the <ulink url="http://www.kernel.org/pub/linux/libs/pam/">
      <productname>Linux-PAM</> Page</ulink>
      and the <ulink url="http://www.sun.com/software/solaris/pam/">
      <systemitem class="osname">Solaris</> PAM Page</ulink>.