Hi All

I have a field that needs to be checked for validity.
It can only contain a-z A-Z 0-9 . _ -
But  . _ - characters cannot be at the begining of the field, and the field can not be just 0-9 or contain 0-9 as the first character i.e:

OK:
billy.bob
billy_bob
billy-bob
billybob
BILLYBOB
BillyBob
Billy2Bob
BillyBob2

NOT OK:
______
_billybob
1billybob
1111
billy^bob

Basicaly, i need to check a name is vaild before passing it over to the unix command 'useradd'.

I have had a go at it myself and looked at some of the tutorials, but no suck luck :-( Thanks

In reply to stuck on regexp by jimbobn

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