On VM/CMS systems, RZ files should always have mode 6, i.e. ``update in place''. In addition, if a file is to be written by one user and simultaneously read by another, the 'F' option of RZMAKE is recommended. If this is not used, users reading the file will not see consistant information if the file is extended, unless the file is first closed and they reaccess the appropriate disk.
The RZOPEN routine should always be used to open an RZ file on VM/CMS systems, to ensure that more than the VS Fortran default of 50 records can be read and written.