13 Environment Variables
The units program uses the following environment variables:
- Specifies the location of your home directory; it is used by
units to find a personal units data file ‘.units’. On
systems running Microsoft Windows, the file is ‘unitdef.units’, and
if HOME does not exist, units tries to determine your
home directory from the HOMEDRIVE and HOMEPATH environment
variables; if these variables do not exist, units finally tries
USERPROFILE—typically C:\Users\username (Windows
Vista and Windows 7) or
C:\Documents and Settings\username (Windows XP).
- LC_CTYPE, LANG
- Checked to determine the locale if units cannot obtain it
from the operating system. Sections of the
standard units data file are specific to certain locales.
- Specifies your personal units data file. If this variable exists,
units uses its value rather than searching your home
directory for ‘.units’. The personal units file will not be
loaded if any data files are given using the ‘-f’ option.
- Specifies the pager to use for help and for displaying the conformable
units. The help function browses the units database and calls
the pager using the ‘+n’n syntax for specifying a line
number. The default pager is more; PAGER can be used
to specify alternatives such as less, pg,
emacs, or vi.
- Set to either ‘US’ or
‘GB’ to choose United States or British volume definitions,
overriding the default from your locale.
- Specifies the units data file to use (instead of the default).
You can only specify a single units data file using this environment
variable. If units data files are given using the -f option,
the file specified by UNITSFILE will be not be loaded unless the
-f option is given with the empty string
(‘units -f ""’).
- Windows only; this variable has no effect on Unix-like systems.
Specifies the units locale map file to use (instead of the default).
This variable seldom needs to be set, but you can use it to ensure that
the locale map file will be found if you specify a location for the
units data file using either the -f option or the
UNITSFILE environment variable, and that location does not also
contain the locale map file.