bzip2 is a freely available, patent free [(see README in the distribution kit)], high-quality data compressor. It typically compresses files to within 10% to 15% of the best available techniques (the PPM family of statistical compressors), whilst being around twice as fast at compression and six times faster at decompression.
BZIP2 is a UNIX-oriented utility, and as such, it has little hope of dealing well with RMS files whose record format is anything other than Stream_LF.
For a more versatile compressor-archiver with greater RMS capability, see the Info-ZIP Home Page.
/ftp/bzip2/bzip2-1_0_5a_vms/vms_notes.txt
Note that support for extended file names on ODS5 file systems depends on fairly recent C RTL features, as found in VMS V7.3-2 or VMS V7.3-1 with VMS731_ACRTL V3.0.
/ftp/bzip2/bzip2-1_0_5a_vms/bzip2-1_0_5a_vms.zip
The Zip archive for this kit was created using the Zip "-V" option to preserve the VMS file attributes, but the source files in this Zip archive should be usable on a non-VMS system. The VMS port notes mentioned above (and included in the kit) describe how to restore the original mixed-case and/or multi-dot file names in the kit which have been altered to accomodate the more limited VMS ODS2 file system where this work was done.
All versions of BZIP2 for VMS, including older and experimental ones, may be found at the archive: /ftp/bzip2/
FTP access is also available at: ftp://ftp.antinode.info/bzip2/