Need help incorporating "strlen"

[Aaron1]

I would like to set the maximum characters using STRLEN in this piece of code:
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$result = mysql_query("SELECT title, threadid, dateline FROM thread WHERE forumid NOT IN ('10','12')ORDER BY dateline DESC LIMIT 40");

while($row = mysql_fetch_assoc($result))

{
echo "<tr><td><a onFocus=\"if(this.blur)this.blur()\" class=\"cap\" href=\"javascript:;\" onClick=\"opener.location='/forum/showthread.php?s=&threadid=".$row["threadid"]."'\">".$row["title"]."</a></td></tr>\r\n";

}

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Because i would like to limit the number of characters .$row["title"] puts out.

I hope you can help out, because i haven't got a clue how to start.