I installed on Ubuntu 16.10 the co-existing php packages as outlined in https://askubuntu.com/questions/761713/how-can-i-downgrade-from-php-7-to-php-5-6-on-ubuntu-16-04
I've run apt-get update and apt-get upgrade. When I try to install php-curl I get an error message:
randall@randall-VirtualBox3:/$ sudo apt-get install php5.6-curl
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package php5.6-curl
E: Couldn't find any package by glob 'php5.6-curl'
E: Couldn't find any package by regex 'php5.6-curl'
randall@randall-VirtualBox3:/$ php -v
PHP 5.6.30-12~ubuntu16.10.1+deb.sury.org+1 (cli)
Copyright (c) 1997-2016 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies
with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2016, by Zend Technologies
with Xdebug v2.5.4, Copyright (c) 2002-2017, by Derick Rethans
randall@randall-VirtualBox3:/$
How do I fix?