Created SC2066 (markdown)

SC2066.md

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+## Since you double quoted this, it will not word split, and the loop will only run once.
+
+### Problematic code:
+
+    for s in "$(mycommand)"; do echo "$s"; done
+
+### Correct code:
+
+The correct code depends on your intention. Let's say you're in a directory with the files `file.png` and `My cat.png`, and you want to loop over a command that outputs (or variable that contains):
+
+    hello world
+    My *.png
+
+#### Loop over each line without globbing (`hello world`, `My *.png`)
+
+    mycommand | while IFS= read -r s; do echo "$s"; done
+
+#### Loop over each word with globbing (`hello`, `world`, `My`, `file.png`, `My cat.png`):
+
+    # relies on the fact that IFS by default contains space-tab-linefeed
+    for s in $(mycommand); do echo "$s"; done 
+
+#### Loop over each line with globbing (`hello world`, `My cat.png`)
+
+    # explicitly set IFS to contain only a line feed
+    IFS='
+    ' 
+    for s in $(mycommand); do echo "$s"; done 
+
+### Rationale:
+
+You get this warning because you have a loop that will only ever run exactly one iteration. Since you have a loop, you clearly expect it to run more than once. You just have to decide how it should be split up.
+
+### Contraindications
+
+None.