Created SC3063 (markdown)

SC3063.md

@@ -0,0 +1,26 @@
+## In POSIX sh, test -R and namerefs in general are undefined.
+
+### Problematic code:
+
+```sh
+if [ -R foo ]
+then
+  ..
+fi
+```
+
+### Correct code:
+
+POSIX sh has no concept of namerefs. Rewrite your logic to not depend on them, or switch to Bash or Ksh.
+
+### Rationale:
+
+`[ -R name ]` is used to check whether `name` is a `nameref`. Since POSIX sh has no namerefs, either use a shell that does, or rewrite to not need namerefs.
+
+### Exceptions:
+
+None
+
+### Related resources:
+
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!