Question

I have a text file like:

================================================
[Feb 11 2013 13:17:14] - some string here and here
General options - [something]
Line y
================================================
Line 1
Line 2
Line 3
Line 4
Line 5     
Something here. Error message: ReferenceError: applyMetadataTemplate is undefined; line: 625  
Line 7
================================================
[Feb 11 2013 16:07:14] - some string here and here
General options - [something]
Line y
================================================
Line 1
Line 2
Line 3
Line 4
Line 5     
Something here. Error message: ReferenceError: applyMetadataTemplate is undefined; line: 625  
Line 7

Now I want to read this file backwards and for each Error that I find inside a record with a new date, I need to do something. I need help 1) reading the file backwards until I encounter the date and saving that date, 2) Grabbing all the lines until then as a string and finding the word Error inside it.
Note: Each record may have different number of lines and may not necessarily have the word error inside it. It’s more a “finding and matching the date and then finding error inside that record” type of problem.

Answer 1

$matches = array();    
$file = file("log.txt");
$file = array_reverse($file);
foreach($file as $f){
    if (stripos($f, "[") !== false) { 
        // Check string for date by regex 
        preg_match('/(\D*) (\d{2}) (\d{4})/', $f, $matches);

        // Check that parts of the date were found
        if(count($matches) > 2) {
            echo $f; //print the line
            break;
        }
    }
}

Read a file, and convert it into an array, then reverse the array for backward traversal, then print out the last date.