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+====== Stripping Comments and Newlines ======
+<code bash>
+cat /etc/squid/squid.conf| sed -e 's/^#.*//g' | sed -e ':r;N;s/\n$//g;br'
+</code>
+First part:
+<code bash>
+sed -e 's/^#.*//g'
+</code>
+strips any line beginning (''^'') with ''#'' and anything that follows after the hash.
+Next part:
+<code bash>
+sed -e ':r;N;s/\n$//g;br'
+</code>
+  - create register ''r'',
+  - put newline (''N'') in register r,
+  - substitute all ending newlines (''\n$'') with nothing ''/''''/'',
+  - repeat with register ''r''.
+====== Insert a Space After Every Character ======
+Using bash:
+<code bash>
+cat test | sed -s 's/\([a-zA-Z0-9]\)/\1 /g'
+</code>
+Note that ''sed'' needs the grouping operators ''('' and '')'' escaped.
+====== Insert a Line at a Given Position ======
+Suppose we have a text file containing the following lines:
+<code>
+number 1
+number 3
+</code>
+and that we want to insert ''number 2'' as the second line between ''number 1'' and ''number 3'', we would issue:
+<code bash>
+sed -i '2inumber 2' file.txt
+</code>
+where the parts of the fragments represent:
+  * ''2'' the line number,
+  * ''i'' for the insert command, and
+  * ''number 2'' the data that has to be inserted.
+which will modify the file in-place such that the contents of the file after the insertion becomes:
+<code>
+number 1
+number 2
+number 3
+</code>
+====== Print all Lines Between Bounds ======
+To print out all the lines between ''5'' and ''10'', issue:
+<code bash>
+sed -n '5,10p' file.txt
+</code>
+====== Normalizing Paths ======
+One way to normalize filenames is to pass the name through the streamline editor, sed:
+<code bash>
+echo "/path/to/file.txt" | LANG=C sed "s/[^\x20\x30-\x39\x40-\x5a\x61-\x7a\x2f\x5c\x5b\x5d]//g"
+</code>
+in order to remove unwanted characters.
+The hexadecimal set that ''sed'' matches in the example corresponds to all characters ''0'' to ''9'', ''a'' to ''z'', ''A'' to ''Z'' plus space, the forward- and backward slashes as well as the square brackets that are used typically to store the YouTube ID within the filename.