--- c: Copyright (C) Daniel Stenberg, , et al. SPDX-License-Identifier: curl Title: CURLINFO_EARLYDATA_SENT_T Section: 3 Source: libcurl See-also: - curl_easy_getinfo (3) - curl_easy_setopt (3) Protocol: - TLS TLS-backend: - GnuTLS Added-in: 8.11.0 --- # NAME CURLINFO_EARLYDATA_SENT_T - get the number of bytes sent as TLS early data # SYNOPSIS ~~~c #include CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_EARLYDATA_SENT_T, curl_off_t *amount); ~~~ # DESCRIPTION Pass a pointer to an *curl_off_t* to receive the total amount of bytes that were sent to the server as TLSv1.3 early data. When no TLS early data is used, this reports 0. TLS early data is only attempted when CURLSSLOPT_EARLYDATA is set for the transfer. In addition, it is only used by libcurl when a TLS session exists that announces support. The amount is **negative** when the sent data was rejected by the server. TLS allows a server that announces support for early data to reject any attempt to use it at its own discretion. When for example 127 bytes had been sent, but were rejected, it reports -127 as the amount "sent". # %PROTOCOLS% # EXAMPLE ~~~c int main(void) { CURL *curl = curl_easy_init(); if(curl) { CURLcode res; curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); /* Perform the request */ res = curl_easy_perform(curl); if(!res) { curl_off_t amount; res = curl_easy_getinfo(curl, CURLINFO_EARLYDATA_SENT_T, &amount); if(!res) { printf("TLS earlydata: %" CURL_FORMAT_CURL_OFF_T " bytes\n", amount); } } } } ~~~ # %AVAILABILITY% # RETURN VALUE Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.