warning about the larger closure

shell_scripts/most_used_commands

@@ -1,7 +1,8 @@
 #! /usr/bin/env bash
 AVOID="con\|utopiah@benetou.fr"
 
-echo consider also http://fabien.benetou.fr/Tools/ and exercises
+echo consider also http://fabien.benetou.fr/Tools/ and to do exercises
+# warning, do not miss the environment e.g. http://mywiki.wooledge.org/BashGuide/
 
 cat ~/.bash_history | sed "s/ /\n/g" | grep "^[[:alpha:]]" | sort | uniq -c | grep -v $AVOID | sort -n | tail | sed "s, \([a-zA-Z].*\), \1\t( http://unixhelp.ed.ac.uk/CGI/man-cgi?\1 ) ,"
 # simpler version for just the first word, which is bad for commands like sort which never appear first