Output last file lines in reverse order- from last to first- in PHP

Question

Looking for a PHP solution to:

1. Perform 'tail' type shell command on a file
2. Perform 'tac' type shell command on a file

In other words, display the last lines of a file in reverse order, from last to first, like a log reader.

I just asked this question for Bash, hoping I could run a shell_exec(), but the recommended method - tac - doesn't work on my OSX.

Answer 1

Take a look at http://php.net/manual/en/function.array-reverse.php

A non-efficient way would be to fgets() the whole file into an array and then reverse it (Not good on big files).

OR

http://tekkie.flashbit.net/php/tail-functionality-in-php

Answer 2

You can get the functionality of tac on OSX by using the -r option to tail

tail -r file
Line3
Line2
Line1