Specify oauth 2 access token
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XOAUTH2_BEARER, char *token);
Pass a char * as parameter, which should point to the zero terminated OAuth 2.0 Bearer Access Token for use with IMAP, POP3 and SMTP servers that support the OAuth 2.0 Authorization Framework.
Note: The user name used to generate the Bearer Token should be supplied via the CURLOPT_USERNAME(3) option.
IMAP, POP3 and SMTP
Added in 7.33.0
Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.