postgresql.conf and postgres options

I've just been looking through the options which can and cannot be set in
postgresql.conf and have a few points to raise.

1.  There are some undocumented options which appear to relate to WAL:
       Name            Variable        Default        Set by
checkpoint_timeout    CheckPointTimeout    300        Startupwal_buffers        XLOGbuffers        8
Startupwal_files       XLOGfiles        0        Startupwal_debug        &XLOG_DEBU        0
Superusercommit_delay       &CommitDelay        5        User
 
   Is there any text anywhere to explain what these do? (Point me to that or   some commented code, and I'll write a
documentationpatch.)
 

2.  The following command line options to postgres don't have an equivalent in   postgresql.conf.  Is that intentional?
(I suppose it is in several cases,   and I have left out some where it is obviously intentional.)  I can't see   why
theseitems can't be put in the configuration file:
 

Option        Action
-C        Noversion = true   [not documented in postgres man page]-D        potential_Datadir = arg      [set PGDATA]-E
      EchoQuery = true   [echo queries to log]-e        EuroDates = true   [use European format for dates]-N
UseNewLine= 0     [newline is not a query separator]-o        [set stdout, stderr to file arg]
 

3.  I see the -E is documented as being for stand-alone mode only; in fact it   is useful for getting the query into
thebackend log in normal operation.
 

4.  The documentation for -o is confusing:
-o file-name
Sends all debugging and error output to OutputFile. If the backendis running under the postmaster, error messages are
stillsent tothe frontend process as well as to OutputFile, but debugging outputis sent to the controlling tty of the
postmaster(since only one    file descriptor can be sent to an actual file).
 
   I think this is saying that, under the postmaster, debugging output does   not get sent to OutputFile, and error
messagesare sent both to OutputFile   and to the frontend.  Is that correct?
 

-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
PGP: 1024R/32B8FAA1: 97 EA 1D 47 72 3F 28 47  6B 7E 39 CC 56 E4 C1 47
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839  932A 614D 4C34 3E1D 0C1C
========================================   "Enter into his gates with thanksgiving, and into his      courts with
praise.Be thankful unto him, and bless      his name."           Psalms 100:4