The error message 'error memcached support requires libmemcached' occurs when there is an attempt to install or use the Memcached PHP extension, but the required supporting library 'libmemcached' is not installed on the system. The Memcached PHP extension depends on 'libmemcached,' which is a C/C++ library for Memcached client development. Without this library, the Memcached PHP extension cannot function properly, leading to the error.
To resolve this error, you need to install the 'libmemcached' library on your system. The installation may vary depending on your operating system and package manager. For example, if you are using Ubuntu, you can install 'libmemcached-dev' by running the following command:
sudo apt-get install libmemcached-dev
After installing the library, you will need to recompile the Memcached PHP extension, which should now work without any errors. Another alternative would be to use a Memcached PHP library that doesn't rely on 'libmemcached.' However, this may come with its trade-offs and limitations, and it's usually better to use the official Memcached PHP extension with 'libmemcached' as a supporting library.