php Curl vs postman giving different results on error - php

Question

I have a php curl script that returns the results of a get the run as a command from another process. The code is:
<?php
$arr = getopt("f:");
$url = $arr['f'];
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5);
curl_setopt($ch, CURLOPT_FAILONERROR, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true );
$result = curl_exec($ch);
if (curl_errno($ch)) {
echo curl_error($ch);
} else {
echo $result;
}
curl_close($ch);
?>
When I do a api get request for a specific url with curl that gives a 400 error, curl_error($ch) is "The requested URL returned error: 400 Bad Request"
When I run the same request in postman, I get a json reply such as: {"result_ok":false,"code":400,"message":"Invalid Email: xxxxxxxxxx#ail.com (POST)"}.
How can I get the json returned in the curl request? If I echo the $result when there is an error condition, it is null.

Answer 1

From CURLOPT_FAILONERROR explained:
fail the request if the HTTP code returned is equal to or larger than 400. The default action would be to return the page normally, ignoring that code.
CURLOPT_FAILONERROR is false by default so either remove it or set it:
curl_setopt($ch, CURLOPT_FAILONERROR, false);