removing directories or if more than 3 files are listed in the
command line.
This feature is intended to provide a safe net but not being too
annoying like having "rm -i" for every deleting operations, and
is generally good for both newbies and power users, preventing
them from being so easily run into ``rm -rf /'', ``rm -rf *''
and so forth.
Originally implemented by Matthew Dillon for DragonFly, plus
some improvements done by various DragonFly contributors.
Approved by: murray (mentor; the original dillon's version)
Discussed with: des
Obtained from: DragonFly's bin/rm/
rm.c rev. 1.4 - 1.8
rm.1 rev. 1.3 - 1.4
MFC After: 1 month