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+## -m will be ignored for parent directories
+
+### Problematic code:
+
+```sh
+mkdir -p -m 0755 foo/bar/baz
+```
+
+### Rationale:
+
+When using `-m 0755`, the mode of the directory created will be set to 0755. When using `-p`, parent directories which do not exist will be created, but the mode specified by `-m` will only be used on the non-parent directory. The parent directories will get their access mode the default way, via [umask(2)].
+
+[umask(2)]: http://man7.org/linux/man-pages/man2/umask.2.html
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