$ mkdir dir
$ cd dir
$ sleep 999 & pid=$!
[1] 13991
$ cd ..
$ rmdir dir
$ mkdir dir
$ touch dir/newfile
$ ls -ld /proc/$pid/cwd
lrwxrwxrwx 1 [...] /proc/13991/cwd -> /home/adeason/dir (deleted)
$ ls /proc/$pid/cwd/
$ ls dir
newfile
$