ref: d06e2d493de522d9c1d91e2d96c3b01c4510b9a7
dir: /rc/bin/dircp/
#!/bin/rc
# dircp src dest - copy a tree with tar
switch($#*){
case 2
@ {builtin cd $1 && tar cif /fd/1 .} | @ {builtin cd $2 && tar xTf /fd/0}
case *
echo usage: dircp from to >[1=2]
exit usage
}