Sticky bit on directories

      bri$ umask 027
      bri$ mkdir /data/pictures ; cd /data/pictures ;
      bri$ cp /mnt/camera/img* . ; ls -la 
      drwxrws---    2 bri     family    4096 Apr 19  4:43 .
      -rw-r-----    1 bri     family  527244 Apr 19  4:43 img102883.jpg
      -rw-r-----    1 bri     family  462312 Apr 19  4:43 img102884.jpg
      
      bree$ cd /data/pictures
      bree$ cp ~/pictures/scan* .
      bree$ ls -l
      -rw-r-----    1 bri     family  527244 Apr 19  4:43 img102883.jpg
      -rw-r-----    1 bri     family  462312 Apr 19  4:43 img102884.jpg
      -rw-rw-r--    1 bree    family 1364772 Sep 17 12:20 scan-01.tiff
      -rw-rw-r--    1 bree    family 2001827 Sep 17 12:20 scan-02.tiff
      
      reegen$ cd /data/pictures
      reegen$ rm *2*
      reegen$ ls -l 
      -rw-rw-r--    1 bree    family 1364772 Sep 17 12:20 scan-01.tiff