CHMODing

hey ya, just wondering now,

Is it possible to CHMOD a file / Set file permissions with PHP?

Cuz my web application needs to write sum values to a config file, & after its done, i would like to set the chmod to 755, and when i need to write to the file set it to 777...

anyhow, lemme no plz :)

Code:

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chmod ("filename", 0755);

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