When variable PWD changed, the behavior of pwd is unspecified http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pwd.html#tag_20_97_08
-- Mr. LE Manh CuongMobile: +84 1216 181090Skype: manhcuongle> From: 446240...@qq.com > Subject: `pwd' returns a dot > Date: Wed, 16 Sep 2015 15:51:08 +0800 > To: bug-bash@gnu.org > > $ cd / > $ PWD=. bash -c pwd > . > $ PWD=. ksh -c pwd > / > > Posix says that pwd shouldn't return the filenames dot or dot-dot. > http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pwd.html >
