ANONYMOUS Will, you really don't need to remember the code rule when you're using chmod command. Instead you can use 'u'ser, 'g'roup, 'o'thers and 'a'll, with plus '+'/minus '-' and 'r'ead, 'w'rite, e'x'ecutable flags to indicate each bit. For example, 'g+r' means it can be read by group; 'o-w' means it can not be written by other users. It's much easier to use, and it's based on the current status: you don't need to 'ls -la' first to acquire the current state first. You will need chmod code only when coding.
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