Question

$ is not matching a position immediately before a newline that is the last character.

Ideally /1…$/ should match but match happens with the pattern /1….$/ which seems to be wrong.

What could be the reason?

PHP doc also says A dollar character ($) is an assertion which is TRUE only if the current matching point is at the end of the subject string, or immediately before a newline character that is the last character in the string (by default).

$subject = 'abc#
123#
';
$pattern = '/1...$/';
preg_match_all($pattern,$subject,$matches); // no match

Update:
I suspect extra dot due to \r\n format of newline.
I did following experiment and see some hint.

$pattern = '/1...(.)$/';

echo bin2hex($matches[1]); // 28

28 seems to be equal to \r (CR) so basically $ is matching before \n not before \r\n, that may be the reason of my problem.

Image after non printable character turn on

Answer 1

Issue was due to different newline representation of window file and linux file

Why this issue:

• I created php file in window and transferred to linux where PHP was installed.
• Windows uses \r\n to represent newline and linux \n ==> that’s why initially it was taking extra dot to match.

Below experiment confirmed the same:

$subject = 'abc#
123#
';
$pattern = '/1...(.)$/';
preg_match_all($pattern,$subject,$matches);
echo bin2hex($matches[1]); // 28 
// 28 is equivalent of \r or CR(carriage return)

Created new file in linux system and /1…$/ catches the match 🙂

I hope this will save someone’s time if stuck with same problem.