====== SED - Delete - Delete BOTH leading and trailing whitespace from each line ======

<code bash>
sed 's/^[ \t]*//;s/[ \t]*$//'
</code>

<WRAP info>
**NOTE:**  Aligns all text flush left.
</WRAP>


<WRAP info>
**NOTE:**  The expression '\t' is used to indicate a tab character (0x09) in the scripts.

Some versions of sed do not recognize the '\t' abbreviation, so when typing these scripts from the command line, you should press the TAB key instead.

'\t' is supported as a regular expression.

</WRAP>

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===== Example =====

Running that command again this file:

<file bash testfile>
aaa
 bbb
  ccc
</file>

returns:

<file bash testfile>
aaa
bbb
ccc
</file>


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===== Example =====

<code bash>
cat input.txt | sed 's/^[ \t]*//;s/[ \t]*$//' > output.txt
</code>

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===== Example - Remove all whitespace (including tabs) from beginning of string =====

<code bash>
echo "     This is a test" | sed -e 's/^[ \t]*//'
</code>

result:

<code bash>
This is a test
</code>

Where,

  * **s/** : Substitute command ~ replacement for pattern (^[ \t]*) on each addressed line
  * **^[ \t]*** : Search pattern ( ^ – start of the line; [ \t]* match one or more blank spaces including tab)
  * **//** : Replace (delete) all matched pattern


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