@c This option is included at several places.
@item --homedir @var{dir}
@opindex homedir
@efindex GNUPGHOME
@efindex HKCU\Software\GNU\GnuPG:HomeDir
Set the name of the home directory to @var{dir}. If this option is not
used, the home directory defaults to @file{~/.gnupg}.  It is only
recognized when given on the command line.  It also overrides any home
directory stated through the environment variable @env{GNUPGHOME} or
(on Windows systems) by means of the Registry entry
@var{HKCU\Software\GNU\GnuPG:HomeDir}.

On Windows systems it is possible to install GnuPG as a portable
application.  In this case only this command line option is
considered, all other ways to set a home directory are ignored.

@efindex gpgconf.ctl
To install GnuPG as a portable application under Windows, create an
empty file named @file{gpgconf.ctl} in the same directory as the tool
@file{gpgconf.exe}.  The root of the installation is then that
directory; or, if @file{gpgconf.exe} has been installed directly below
a directory named @file{bin}, its parent directory.  You also need to
make sure that the following directories exist and are writable:
@file{ROOT/home} for the GnuPG home and @file{ROOT@value{LOCALCACHEDIR}}
for internal cache files.