variable quoting for $HOME with spaces. seems like it works.

z.sh

@@ -39,8 +39,8 @@ z() {
      for( i in rank ) print i "|" 0.9*rank[i] "|" time[i] # aging
     } else for( i in rank ) print i "|" rank[i] "|" time[i]
    }
-  ' $datafile 2>/dev/null > $datafile.tmp
-  mv -f $datafile.tmp $datafile
+  ' "$datafile" 2>/dev/null > "$datafile.tmp"
+  mv -f "$datafile.tmp" "$datafile"
  elif [ "$1" = "--complete" ]; then
   # tab completion
   awk -v q="$2" -F"|" '
@@ -58,7 +58,7 @@ z() {
      if( $1 ) print $1
     }
    }
-  ' $datafile 2>/dev/null
+  ' "$datafile" 2>/dev/null
  else
   # list/go
   while [ "$1" ]; do case "$1" in
@@ -132,11 +132,11 @@ z() {
      output(wcase, cx, common(wcase, a, 0))
     } else if( ncx ) output(nocase, ncx, common(nocase, a, 1))
    }
-  ' $datafile)"
+  ' "$datafile")"
   if [ $? -gt 0 ]; then
-   rm -f $datafile.tmp
+   rm -f "$datafile.tmp"
   else
-   mv -f $datafile.tmp $datafile
+   mv -f "$datafile.tmp" "$datafile"
    [ "$cd" ] && cd "$cd"
   fi
  fi