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copied!<p>Awk is appropriate for this problem domain because the text file is already (more or less) organized into columns. Here's what I would use:</p> <pre><code>awk 'NF == 3 && index($2, "=") { filename = substr($2, index($2, "=") + 1) } NF == 2 && filename { print $0 > (filename ".txt") }' < input.txt </code></pre> <p>Explanation:</p> <p>Think of the lines starting with <em>variableStep</em> as "three columns" and the other lines as "two columns". The above script says, "Parse the text file line-by-line; if a line has three columns and the second column contains an '=' character, assign 'all of the characters in the second column that occur after the '=' character' to a variable called <code>filename</code>. If a line has two columns and the <code>filename</code> variable's been assigned, write the entire line to the file that's constructed by concatenating the string in the filename variable with '.txt'".</p> <p>Notes:</p> <ul> <li><strong>NF</strong> is a built-in variable in Awk that represents the "number of fields", where a "field" (in this case) can be thought of as a column of data.</li> <li><strong>$0</strong> and <strong>$2</strong> are built-in variables that represent the entire line and the second column of data, respectively. (<strong>$1</strong> represents the first column, <strong>$3</strong> represents the third column, etc...)</li> <li><strong>substr</strong> and <strong>index</strong> are built-in functions described here: <a href="http://www.gnu.org/software/gawk/manual/gawk.html#String-Functions" rel="nofollow">http://www.gnu.org/software/gawk/manual/gawk.html#String-Functions</a> The <strong>redirection operator (>)</strong> acts differently in Awk than it does in a shell script; subsequent writes to the same file are appended.</li> <li>String concatenation is performed simply by writing expressions next to each other. The parenthesis ensure the concatenation happens before the file gets written to.</li> </ul> <p>More details can be found here: <a href="http://www.gnu.org/software/gawk/manual/gawk.html#Two-Rules" rel="nofollow">http://www.gnu.org/software/gawk/manual/gawk.html#Two-Rules</a></p>

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