I'm trying to use PHP and MySQL to query a table and write the contents to a
new file. When run the command to outfile it tells me I don't have
permissions. This is on a Unix machine.
I haven't run this on Unix myself, but I think this answer might be useful. Someone please correct me if I'm out to lunch.
Check which user account is actually running the PHP process (or the Apache process if it's not the CGI). Then ensure that it (the PHP user) has the rights to create files in the specified directory.
Be careful here though, because you will be giving malicious visitors more tools to work with.
Cheers,
-Peter