Created SC1138 (markdown)

SC1138.md

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+## Shells are space sensitive. Use '< <(cmd)', not '<< (cmd)'.
+
+### Problematic code:
+
+```sh
+while read -r line
+do
+  echo "You said: $line"
+done <<(cmd)
+```
+
+### Correct code:
+
+```sh
+while read -r line
+do
+  echo "You said: $line"
+done < <(cmd)
+```
+### Rationale:
+
+When redirecting `<` from a process substitution `<(cmd)`, make sure there is a space between the two `<` characters as shown in the example.
+
+With a space `cmd1 < <(cmd2)`, is correctly interpreted as "run cmd1, reading stdin from cmd2, without forking for a pipeline".
+
+Without a space, `<<` is incorrectly considered a here document, and `(cmd2)` is an invalid delimiter token.
+
+
+### Exceptions:
+
+None
+
+### Related resources:
+
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!