How can PHP developers troubleshoot undefined function errors like curl_init()?

When encountering undefined function errors like curl_init(), PHP developers can troubleshoot by checking if the cURL extension is enabled in their PHP configuration. They can do this by looking for 'extension=php_curl.dll' in their php.ini file or using the phpinfo() function to check if the cURL extension is loaded. If the cURL extension is not enabled, developers can enable it by uncommenting or adding the extension directive in their php.ini file and restarting their web server.

// Check if the cURL extension is enabled
if (!function_exists('curl_init')) {
    echo 'cURL extension is not enabled';
    // Uncomment or add the following line in php.ini to enable the cURL extension
    // extension=php_curl.dll
}