Created SC2012 (markdown)

SC2012.md

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+## Use find instead of ls to better handle non-alphanumeric filenames.
+
+### Problematic code:
+
+    ls -l | grep " $USER " | grep '\.txt$'
+
+### Correct code:
+
+    find . -maxdepth 1 -name '*.txt' -user "$USER" 
+
+### Rationale:
+
+`ls` is only intended for human consumption: it has a loose, non-standard format and may "clean up" filenames to make output easier to read.
+
+Here's an example:
+
+    $ ls -l
+    total 0
+    -rw-r----- 1 me me 0 Feb  5 20:11 foo?bar
+    -rw-r----- 1 me me 0 Feb  5  2011 foo?bar
+    -rw-r----- 1 me me 0 Feb  5 20:11 foo?bar
+
+It shows three seemingly identical filenames, and did you spot the time format change? How it formats and what it redacts can differ between locale settings, `ls` version, and whether output is a tty. 
+
+`ls` can usually be substituted for `find` if it's the filenames you're after.
+
+If trying to parse out any other fields, first see whether `stat` (GNU, OS X, FreeBSD) or `find -printf` (GNU) can give you the data you want directly. 
+
+### Exceptions:
+
+If the information is intended for the user and not for processing (`ls -l ~/dir | nl; echo "Ok to delete these files?"`) you can ignore this message (add a [[directive]]).