Created SC2232 (markdown)

SC2232.md

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+## Can't use sudo with builtins like cd. Did you want sudo sh -c .. instead?
+
+### Problematic code:
+
+```sh
+sudo cd /root
+pwd
+```
+
+### Correct code:
+
+```sh
+sudo sh -c 'cd /root && pwd'
+```
+### Rationale:
+
+Due to the Unix process model, `sudo` can only change the privileges of a new, external process. It can not grant privileges to a currently running process.
+
+This means that shell builtins -- commands that are interpreted by the current shell rather than through program invocation -- cannot be run with `sudo`. This includes `cd`, `source`, `read`, and others.
+
+Instead you can run a shell with `sudo`, and have that shell run the builtins you want. Just be aware that what happens in that shell stays in that shell:
+
+    sudo sh -c 'cd /root && pwd'  # This shows /root
+    pwd                           # This shows the original directory
+
+### Exceptions:
+
+None.
+
+### Related resources:
+
+* [SuperUser](https://superuser.com/questions/241129/why-wont-sudo-cd-work): Why won't “sudo cd” work?
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!