Help with File rights

Anon

ok my knowledge is limited but please bear with me. OK our Database is a Library of Documents that we have created, there are many different companys that created different documents. How I would like to set it up is we have a group of people that are in a project together that have READ access but not WRITE, that is resvered for the Author. What I have to have is two files (DOC , And PDF) that are have Write Access to Author but only Read to the Group, and nothing to everyone else.

EX.

Group on file xxx.doc
(Scott, Sally)
Scott and Sally can read the file but not Write

Author on file xxx.doc
(Jim)
Jim can change and modify the file as he pleases.

Im using Postgres 7.1 with PHP 4.03 on a Redhat Linux 6.2 BOX

I hope that I have explained myself well if not please fell free to ask questions.

Thanks you in advance

[deleted]

So I take it you will be uploading the documents through a php web page?

Anon

yes that is correct but also I will need to set the permission on the existing files, is there anything that you can help me with

[deleted]

If it's all through a webpage, then you don't actually set permissions on the files themselves.
Instead, you give your users usernames and passwords with which they can login to the page that lets them up and download.
Then, when they want to download files, you'll have to write a script that will look in the database to see if that user has access to that file.
If so, you let PHP read the file and pass it to the user.
If not, you print a polite "sorry" message.
The same thing would work for uploading, but the trouble is, you can't tell what the filename of the uploaded file is untill it has been uploaded (not stored, just oploaded). So if someone uploads a 40 MB file, he won't find out he's not allowed untill he has uploaded all 40MB.
Once the file is uploaded, you can check the permissions for that file. If permission is granted, you save the file. I not, print a sorry message.

There is more than enough info on this very site (read the articles and tips) to get you started.