“use chroot” in the rsync.conf

[Qian Hao]

hello everyone,
I am a little confused by the "use chroot "setting in the rsyncd.conf.
In the manpages, it says that

"As  an  additional safety feature, you can specify a dot-dir in the
module's "path" to indicate
 the point where the chroot should occur.  This allows rsync to run in
a chroot with  a  non-"/"
 path for the top of the transfer hierarchy.  Doing this guards
against unintended library load-
 ing (since those absolute paths will not be inside the transfer
hierarchy unless you have  used
 an unwise pathname), and lets you setup libraries for the chroot that
are outside of the transfer. "

what does the "Doing this" mean ? Does it mean that "specify a dot-dir
in the module's "path" " ?
I can not figure out it's safer to specify a dot-dir in the module's "path".
--
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        敬礼！