if its a parameter for some shell code, then you need to douple escape the escapest. If I remember correctly, if you need an escape char in a string, you can put it in with \\, but if you need to put an escape char to a string which will be executed via exec/system/etc. then you have to put an escaped escape char, so in the end you need four escape char. correct me, if Im wrong. Tyrael On Mon, Jan 11, 2010 at 2:37 AM, Mark Murphy <mmurph@xxxxxxxxxxxx> wrote: > Can someone interpret this preg string for me? > > /[^a-z0-9\\/\\\\_.:-]/i > > Here is what I can decipher. the match is case insensitive, and it excludes > all letters, and numbers, and the characters _ . : and - (that is > underscore, period, colon, and dash). The part I don't understand is > \\/\\\\. Sees to me to say backslash, slash, backslash, backslash. Why the > need for so many backslashes? > > -- > PHP Windows Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > > -- PHP Windows Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php