Detecting file mode in PHP

[aguilanegra]

I am looking for a way in PHP to detect the mode of a file prior to making mode changes to it.

I would like to perform the following (in pseudocode):

if (fileMode == "644") {
chmod(fileName, 0775);
make changes here
chmod(fileName, 0664);
else
do nothing
end if

I realize that this requires certain permissions to do this, so I also need assistance in determining what the PHP script's permissions are, so I can set them properly prior to running.

[ereptur]

Not sure how to check permissions on a file, but I can tell you that your scripts are run as the user that the web server is setup as. What permissions your web server has are passed on to your script.