PWD to Titlebar

gistfile1.txt

function directory_to_titlebar { 
   local pwd_length=42  # The maximum length we want (seems to fit nicely 
                        # in a default length Terminal title bar). 
   # Get the current working directory.  We'll format it in $dir. 
   local dir="$PWD" 
 
   # Substitute a leading path that's in $HOME for "~" 
   if [[ "$HOME" == ${dir:0:${#HOME}} ]] ; then 
       dir="~${dir:${#HOME}}" 
   fi 
 
   # Append a trailing slash if it's not there already. 
   if [[ ${dir:${#dir}-1} != "/" ]] ; then 
       dir="$dir/" 
   fi 
 
   # Truncate if we're too long. 
   # We preserve the leading '/' or '~/', and substitute 
   # ellipses for some directories in the middle. 
   if [[ "$dir" =~ (~){0,1}/.*(.{${pwd_length}}) ]] ; then 
       local tilde=${BASH_REMATCH[1]} 
       local directory=${BASH_REMATCH[2]} 
 
       # At this point, $directory is the truncated end-section of the 
       # path.  We will now make it only contain full directory names 
       # (e.g. "ibrary/Mail" -> "/Mail"). 
       if [[ "$directory" =~ [^/]*(.*) ]] ; then 
           directory=${BASH_REMATCH[1]} 
       fi 
 
       # Can't work out if it's possible to use the Unicode ellipsis, 
       # '…' (Unicode 2026).  Directly embedding it in the string does not 
       # seem to work, and \u escape sequences ('\u2026') are not expanded. 
       #printf -v dir "$tilde/\u2026$s", $directory" 
       dir="$tilde/...$directory" 
   fi 
 
   # Don't embed $dir directly in printf's first argument, because it's 
   # possible it could contain printf escape sequences. 
   printf "\033]0;%s\007" "$dir" 
} 
 
if [[ "$TERM" == "xterm" || "$TERM" == "xterm-color" ]] ; then 
 export PROMPT_COMMAND="directory_to_titlebar" 
fi