Permission denied ?

Welcome to the forums.

A minimal understanding of multi-user operating systems plus file and directory permissions will make this a trivial issue to solve.
Different programs/processes run under different userids. Each different userid has a few different groups. The combination of userid, groupid and process owner are the core of all Unix security. So ... if you want to _understand_ this stuff, begin with working through a permissions tutorial. https://help.ubuntu.com/community/FilePermissions
Some more background on Unix/Linux would be helpful too. Probably not something you need, but perhaps for other lurkers coming from a mainly Windows background:
* http://www.dedoimedo.com/computers/u...ows-users.html
* http://linux.oneandoneis2.org/LNW.htm

I don't know anything about php or mindcraft, but try using absolute paths, not relative paths, to get the startup working - actually, that won't work. The program needs to have execute bits set - use chmod to fix that. Also, if the php program is part of an all-in-one Mindcraft install, I suspect there are other permissions issues either with how the install was unpacked or how the provider packaged it. File and directory permissions are the coerstone for everything. Perhaps you can provide a link to the instructions you were following? I thought mindcraft used java?

If you just want to know _what to type_, then someone else will have to answer. Sorry.