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====== AWK - Display line before the matching string ======

<code bash>
awk '/the_string/{print x};{x=$0}' file.txt
</code>

<WRAP info>
**NOTE:**  This starts at the bottom of the file searching upwards and once it finds the search string it displays everything else above.
</WRAP>

----

====== Example ======

Assuming a file, **test.txt**, exists with the following contents:

<file>
10   Peter     Terence   Roux        45
11   Virginia  Genevieve  Roux        45
12   Felix     Devon     Roux         5
13   David     Bruce     Stevenson   48
14   Bob       James     Smith       16
48   Adam      Winter    Ridley      23
</file>

Running

<code bash>
awk '/Peter/{print x};{x=$0}' test.txt
</code>

returns:

<code bash>

</code>

<WRAP info>
**NOTE:**  As there is no line about row 10, which contains the search string **Peter**, an empty line is added to the result.
</WRAP>


----

Running

<code bash>
awk '/Roux/{print x};{x=$0}' test.txt
</code>

returns:

<code bash>

10   Peter     Terence   Roux        45
11   Virginia  Genevieve  Roux       45
</code>

<WRAP info>
**NOTE:**  As there is no line about row 10, which contains the search string **Roux**, an empty line is added to the result.

Row 11 has the the search string **Roux**, results in the line above, row 10, being added to the result;  even though row 10 also contains the search string.

Row 12 has the the search string **Roux**, results in the line above, row 11, being added to the result;  even though row 10 also contains the search string.

No further rows contain the search string so nothing else is added to the output.
</WRAP>


----

Running

<code bash>
awk '/4/{print x};{x=$0}' test.txt
</code>

returns:

<code bash>

10   Peter     Terence   Roux        45
12   Felix     Devon     Roux         5
13   David     Bruce     Stevenson   48
14   Bob       James     Smith       16
</code>

----