function - PHP echo vs PHP short echo tags

Question

Are they equal in safeness? I was informed that using

<?=$function_here?>

was less safe, and that it slows down page load times. I am strictly biased to using echo.

What are the advantages/disadvantages?

Answer 1

<? and <?= are called short open tags, and are not always enabled (see the short_open_tag directive) with PHP 5.3 or below (but since PHP 5.4.0, <?= is always available).

Actually, in the php.ini-production file provided with PHP 5.3.0, they are disabled by default:

$ grep 'short_open' php.ini-production
; short_open_tag
short_open_tag = Off

So, using them in an application you want to distribute might not be a good idea: your application will not work if they are not enabled.

<?php, on the other side, cannot be disabled -- so, it's safest to use this one, even if it is longer to write.

Except the fact that short open tags are not necessarily enabled, I don't think there is much of a difference.