umask - set the file mode creation mask
umask [MASK]Options you will use
-S- Print the mask in symbolic form: u=rwx,g=rx,o=rx.
Gotchas
- The mask REMOVES bits. 022 gives 644 files and 755 dirs; 027 gives 640 and 750. Directories start from 777, files from 666 - which is why new files are never executable.
Taught in
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