Several programs require input of a set of spacegroup symmetry operators in O format. To make this easier, you can now define an environment variable OSYM which should point to your local directory that contains the collection of spacegroup operator files (usually, $ODAT/symm).
The following programs are sensitive to this variable: AVE, DATAMAN, IMP, MAVE, NCS6D, MAMA, PACMAN and XPAND.
In Uppsala, put the following in your .cshrc file:
setenv OSYM /nfs/taj/alwyn/o/data/symm/
When asked for a file with spacegroup operators in O format, you may either provide a filename, or the name of a spacegroup (including blanks if you like; case doesn't matter). The program will try to open the following files, assuming that STRING is the name you provided:
For instance, if you type "p61.sym", the program will first try to open this file in your current directory. If that fails, it will look for it in the $OSYM directory.
Similarly, typing "P 43 21 2" should result in the program finding the file $OSYM/p43212.sym.
Hint: if you make soft links in the OSYM directory, you can also type spacegroup numbers (e.g.: \ln -s p212121.sym 19). See OMAC news below. Theoretically, this should also allow you to type "19" in the Symm_setup command in O, but I haven't tested this yet.
Hint: use Phil Evans' program gen_o_symm.f (file://rose.bmc.uu.se/pub/gerard/omac/gen_o_symm.f) to generate the complete set of spacegroup operator files from the CCP4 symop.lib file.