This directory contains some files needed to build SDS on a machine that does
not have the DRAMA data acquisition environment installed.

The makefile.standalone file in the main SDS directory makes use of these files.

arg_err.h and arg_err_msgt.h are normally genrated from arg_err.msg using the
DRAMA messgen utility. For use on systems that do not have this utility, these
versions of these files have been generated on a system that does have messgen
available. These files define values and text strings associated with the errors
generated by the arg routines.

sds_err.h and sds_err_msgt.h are the equivalent files generated from sds_err.msg.

Note that if a new error code is added to sds_err.msg or arg_err.msg, these
files will have to be generated anew, probably using messgen.

status.h and drama.h are standard included files used by all DRAMA code, and
define a number of housekeeping things such as a type used to return status
information.

(Previous releases of SDS contained a directory called Standalone, containing
a similar set of files connected with building on systems that did not have
DRAMA installed. However, over the years this collection had become confusing
and mostly irrelevant, supporting systems such as the DEC Alpha and Solaris but
not OS X or Linux. This old directory has been renamed old_standalone, and has
been replaced by this one. It may be that some of the files in the old directory
turn out to still be useful - for example, they included a set of minimal
look-alike Ers library routines, although it is easy enough to build Ers
in a standalone mode now and these are probably no longer necessary.)

(Keith Shortridge, Dec 2020)
