CURLOPTReturnTransfer

CURLOPT_RETURNTRANSFER is a cURL option that, when set to true, instructs the cURL transfer to return the transfer as a string instead of outputting it directly. By default, cURL outputs the transferred data to standard output. Setting this option allows you to capture the response body into a variable for further processing within your application.

When CURLOPTReturnTransfer is used, the curl_exec() function will return the contents of the transfer as a string. If an error occurs during the transfer, curl_exec() will return false. It is essential to check the return value of curl_exec() to ensure the transfer was successful and to handle potential errors.

This option is commonly used in scripting languages like PHP, where you might want to fetch the content of a web page and then parse it, modify it, or store it for later use. For instance, in PHP, you would typically use it like this: curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); after initializing a cURL handle ($ch). The retrieved data would then be available via the result of curl_exec($ch).

Without CURLOPTReturnTransfer, the output of a cURL request would be printed directly to the browser or console, making it difficult to work with programmatically. Therefore, CURLOPTReturnTransfer is a fundamental option for developers who need to integrate web data into their applications.