OMAC is the generic name for a directory containing all sorts of useful O macros, O datablocks, O residue-property tables, C-shell scripts, small Fortran programs etc. etc. All the things in here are public domain and contributions to it are greatly appreciated. I (=gjk) will put in useful macros that are broadcast via the O-Info server on a regular basis.
You will find this directory (tar-ed and compressed) on our ftp-server in file://rose.bmc.uu.se/pub/gerard/omac/omac.dirtar.Z
It is most useful to have a link to this directory in your O work directory !