Creating directories in php with mkdir()

mkdir() php function enables you to create a directory. mkdir() requires a string representing the path to the directory you want to create and an integer that should be an octal number representing the mode you want to set for the directory. You specify an octal (base 8) number with a leading 0. The mode argument has an effect only on Unix systems.

mkdir( "testdir", 0777 ); // global read/write/execute permissions
mkdir( "testdir", 0755 ); // world and group: read/execute only
             // owner: read/write/execute