Rsync-bpc is a customized version of rsync that is used as part of BackupPC,
an open source backup system.

The main change to rsync is adding a shim layer that emulates the system calls
for accessing the file system so that rsync can directly read/write files in
BackupPC's format.

Rsync-bpc is fully line-compatible with vanilla rsync, so it can talk to rsync
servers and clients.

Rsync-bpc serves no purpose outside of BackupPC.

WWW: http://backuppc.sourceforge.net/