mercurial/help/config.txt

backout: make help more explicit about what backout does

The help for backout explains:

   The backout command merges the reverse effect of the reverted
   changeset into the working directory.

Unfortunately, that does not make it obvious to a newcomer what the
backout command does.  Since it performs a 3-way merge, what is the
common ancestor?  Will the result be automatically committed?  What is
this reverted changeset --- is it the rev passed with -r on the
command line or its inverse?

So try to clarify the description, avoiding jargon and being
explicit about what happens from the user's perspective.

Thanks to Gilles Moris, Steve Borho, Kevin Bullock, and timeless for
help.

Mercurial reads configuration data from several files, if they exist.
Below we list the most specific file first.

On Windows, these configuration files are read:

- ``<repo>\.hg\hgrc``
- ``%USERPROFILE%\.hgrc``
- ``%USERPROFILE%\mercurial.ini``
- ``%HOME%\.hgrc``
- ``%HOME%\mercurial.ini``
- ``C:\mercurial\mercurial.ini`` (unless regkey or hgrc.d\ or mercurial.ini found)
- ``HKEY_LOCAL_MACHINE\SOFTWARE\Mercurial`` (unless hgrc.d\ or mercurial.ini found)
- ``<hg.exe-dir>\hgrc.d\*.rc`` (unless mercurial.ini found)
- ``<hg.exe-dir>\mercurial.ini``

On Unix, these files are read:

- ``<repo>/.hg/hgrc``
- ``$HOME/.hgrc``
- ``/etc/mercurial/hgrc``
- ``/etc/mercurial/hgrc.d/*.rc``
- ``<install-root>/etc/mercurial/hgrc``
- ``<install-root>/etc/mercurial/hgrc.d/*.rc``

If there is a per-repository configuration file which is not owned by
the active user, Mercurial will warn you that the file is skipped::

  not trusting file <repo>/.hg/hgrc from untrusted user USER, group GROUP

If this bothers you, the warning can be silenced (the file would still
be ignored) or trust can be established. Use one of the following
settings, the syntax is explained below:

- ``ui.report_untrusted = False``
- ``trusted.users = USER``
- ``trusted.groups = GROUP``

The configuration files for Mercurial use a simple ini-file format. A
configuration file consists of sections, led by a ``[section]`` header
and followed by ``name = value`` entries::

  [ui]
  username = Firstname Lastname <[e-mail]>
  verbose = True

The above entries will be referred to as ``ui.username`` and
``ui.verbose``, respectively. Please see the hgrc man page for a full
description of the possible configuration values:

- on Unix-like systems: ``man hgrc``
- online: http://www.selenic.com/mercurial/hgrc.5.html