Created SC2073 (markdown)

SC2073.md

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+## Escape `\<` to prevent it redirecting (or switch to `[[ .. ]]`).
+
+### Problematic code:
+
+```sh
+if [ "aardvark" < "zebra" ]
+then
+  echo "Alphabetical!"
+fi
+```
+
+### Correct code:
+
+```sh
+if [ "aardvark" \< "zebra" ]
+then
+  echo "Alphabetical!"
+fi
+```
+
+or optionally in Bash/Ksh:
+
+```sh
+if [[ "aardvark" < "zebra" ]]
+then
+  echo "Alphabetical!"
+fi
+```
+### Rationale:
+
+You are using the operator `<` or `>` in a `[` test expression.
+
+In this context, it will be considered a file redirection operator instead, so `[ "aardvark" < "zebra" ]` is equivalent to `[ "aardvark" ] < ./zebra`, which is true if there exists a readable file `zebra` in the current directory.
+
+If you wanted to compare two strings lexicographically (alphabetically), escape the `<` or `>` with a backslash as in the correct example. 
+
+If you want to compare two numbers numerically, use `-lt` or `-ge` instead.
+
+### Exceptions:
+
+None.
+
+### Related resources:
+
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!