yura@yura:~$ ls -a
.                   .bashrc  dir_tree          .face                  .goutputstream-51G14W  .ICEauthority     .mixxx    Pictures       .pulse-cookie  Templates         .xsession-errors.old
..                  .cache   .dmrc             .gconf                 .goutputstream-F8CZ4W  .java             Mixxx     .profile       .Skype         Videos
.adobe              .compiz  Documents         .gnome2                .goutputstream-TBVW4W  java_progs        module    project        .ssh           .viminfo
.apport-ignore.xml  .config  Downloads         .gnome2_private        .goutputstream-Z89K4W  .local            .mozilla  project_final  .swt           workspace
.bash_history       .dbus    .eclipse          .goutputstream-11KV4W  .gstreamer-0.10        .macromedia       Music     Public         syserr.log     .Xauthority
.bash_logout        Desktop  examples.desktop  .goutputstream-1UX14W  .gtk-bookmarks         .mission-control  perl      .pulse         sysout.log     .xsession-errors
yura@yura:~$ perl dir_tree 
.ICEauthority 33170
module 433
project_final 4515
dir_tree 704
.profile 675
project 4486
sysout.log 19807
examples.desktop 8445
syserr.log 2350
.pulse-cookie 256
.xsession-errors.old 828
.viminfo 14093
.bash_history 17965
.face 9447
.bashrc 3637
.bash_logout 220
yura@yura:~$