I am not sure if anyone have the similar issue, 
$a = "/path/to/a/file";
$b = "/path/to/b/file";
$difference = system("$diff $a $b");
$difference2 = system("$diff -y $a $b");

[download]
The $difference printed in html file only shows the difference - top & bottom (maybe 2 or 3 lines from 1000 lines).

But the $difference2 printed in html file shows all the difference in 2 columns -left & right (1000 lines from 1000 lines).

The output is actually fine, since I dont want to compare line by line, as sometime one has some extra lines while the other dont,

So i want those extra lines which is in a and in b at the same file same time.

Here, I am wondering if it is possible to have the sort of combination of both $diff and $diff -y, having 2 left/right columns of difference in some lines only (not showing every lines) 
if ($difference eq ''){
$difference = "Exactly Same.\n";
}
push @table1, "<table id =\"Table1\">";
push @table1, "<tr><th>path A</th><th>A</th><th>path B</th><th>B</th><
+/tr>";
push @table1, "<tr><td colspan =\"4\">$difference</td></tr>";

[download]
So that, $difference will shown in 2 columns with the line of differences in file.

Any idea guys ?

In reply to diff vs diff -y by MissPerl

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