Created SC3031 (markdown)

SC3031.md

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+## In POSIX sh, redirecting from/to globs is undefined.
+
+(or "In dash, ... is not supported." when using `dash`)
+
+### Problematic code:
+
+```sh
+#!/bin/sh
+date > /tmp/log*.txt
+```
+
+### Correct code:
+
+To redirect from/to the only match of a glob, expand the glob first:
+
+```sh
+#!/bin/sh
+set -- /tmp/log*.txt
+# PS: This is a good place to verify that there was exactly one match
+date > "$1"
+```
+
+Alternatively, use a loop to redirect from/to all if that was the intention.
+
+### Rationale:
+
+Shells differ in whether (and how) they do pathname expansion on names in redirections. Avoid the issue by expanding the glob yourself. 
+
+### Exceptions:
+
+If you only intend to target shells that supports this feature, you can change
+the shebang to a shell that guarantees support, or [[ignore]] this warning.
+
+You can use `# shellcheck disable=SC3000-SC4000` to ignore all such compatibility
+warnings.
+
+### Related resources:
+
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!