FTP and chmod

[Anon]

I've got a picture gallery app which has image processing automation. I upload all the new images to a directory via FTP and then run the processing script. Everything works find except I cannot unlink() the original files because I don't have permission (or PHP doesn't have permission). I get the same error when I try to chmod() them. If I copy() the files I can chmod() the copies, but not the originals. Here's the exact error:

Warning: chmod failed: Operation not permitted in /usr/home/www/botono9/aaron-murray.net/docs/Admin/processImages.php on line 70

Here's the code at line 70:

chmod($file, 0777);

I've also tried chmod($file, 0775); but to no avail. Any help would be greatly appreciated. Thanks.

[vsego]

When you upload the image you are some user (let's say amurray). That user is the owner of the file and, therefore, can do chmod (from FTP or SSH).
If you don't want to chmod file so it can be removed (by the way, I think you should chmod directory for this - not individual files), you can put HTTPD and amurray in special user group and play with group options then.

[Anon]

I just chmod'd the dir to 701 (owner - read, write, exec; group - exec; public - null) it lets me read using php scripts, write using php scripts, and exec using php scripts. i used it for a dir called "logs" , unless you are gonna be using mysql or some other program in that dir, just add read and write for groups if thats the case.