Mac – Umask & You!

I recently came across a situation where I had to setup a shared folder on an AIX filesystem. Usually I would use ACLs to setup permission inheritance but there is no ACL support for Mac OS X on an AIX filesystem. So I had to resort to changing the users’ umask.

There are several places where you can specify a umask. There can different different umasks for:

  • Applications (EX: Finder, TextEdit, etc…)
  • Terminal sessions (EX: SSH)
  • System processes
  • LaunchDaemons & LaunchAgents

For most cases you would only need to specify a umask for applications and terminal sessions. However, I’ll cover all after the jump.

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