Allowing only search engines to crawl forums

Only want search engines in my forums

[Psycho111]

I have a phpBB forum that I want to hack so it is search engine friendly. The only problem is that I only want search engines in there, and nothing else. Robots.txt doesn't have an allow directive so I'm not sure how to accomplish this. Would this work:

User-agent: *
Disallow: /phpBB2/

User-agent: googlebot, altavista, scooter, slurp
Disallow:

I'm not sure if I have the user-agents right...it's case sensitive right?

[Brett_Tabke]

no, there is no "allow" format. This is one of the reason many of us say that thet robots.txt format is simply not usable any longer.

[Psycho111]

So there is no way of doing it? If you leave a disallow blank doesn't that mean the user-agent isn't disallowed from anything...so it would override the first disallow?

[DaveAtIFG]

According to the second to last example here [robotstxt.org], what you propose should do what you intend.

I'd watch my logs VERY carefully for a few days to be CERTAIN it's working as intended. ;)

[Psycho111]

Does anyone know the exact user-agents for the popular search engines? Taking Google as an example, would just putting "Googlebot" work or do you need it more specific like "Googlebot/2.0".

[Psycho111]

Does anyone have a list of the major search engine user-agents?

[dvduval]

Quite a few here:
[webmasterworld.com...]