error setting certificate verify locations: CAfile: /etc/pki/tls/certs/ca-bundle.crt

Open terminal ctrl+alt+t and change working directory:

 cd /etc/ssl/certs/

Download pem file in the certs folder

 sudo wget https://curl.se/ca/cacert.pem 

Now open the file .curlrc

nano ~/.curlrc 

Add the below lines in the open file

capath=/etc/ssl/certs/
cacert=/etc/ssl/certs/ca-certificates.crt

Now save the file and do your things using curl command.

This works for me. Just making a symbolic link ln -s /etc/ssl/certs/ca-certificates.crt /etc/pki/tls/certs/ca-bundle.crt

how to detect curl error

curl_setopt($ch, CURLOPT_FAILONERROR, true) // 
$result = curl_exec($ch)
if (curl_errno($ch)) {
	$error_msg = curl_error($ch)
	echo $error_msg
}

or the worst method

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true)
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false)
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false)