add a regression which fails in the current code base.  Haven't hunted all the way down.  Looks like when a push is doing a query to a remote repo (bk -@bk://localhost:1234/crepo _binpool_query -m -) and the remote repo is below the bkd, and to its side, its binpool master is also below the bkd, then unsafe_cd() because the current directory 'a' and the desired directory 'b' are next to each other.
add a regression which fails in the current code base.  Haven't hunted
all the way down.  Looks like when a push is doing a query to a remote
repo (bk -@bk://localhost:1234/crepo _binpool_query -m -) and the remote
repo is below the bkd, and to its side, its binpool master is also below
the bkd, then unsafe_cd() because the current directory 'a' and the
desired directory 'b' are next to each other.

In binpool_query_main(), if -m, then do a 'bk -@<file_url' and the
BKD_DAEMON env is set because the parent process is a bkd, then unsafe_cd
will fail.

bk: 458858f9nGBbuIUAbub_cQ8V_qrIMg
bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper