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.TH CURLOPT_USE_SSL 3 "March 23, 2020" "libcurl 7.73.0" "curl_easy_setopt options"

.SH NAME
CURLOPT_USE_SSL \- request using SSL / TLS for the transfer
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_USE_SSL, long level);
.SH DESCRIPTION
Pass a long using one of the values from below, to make libcurl use your
desired \fIlevel\fP of SSL for the transfer.

These are all protocols that start out plain text and get "upgraded" to SSL
using the STARTTLS command.

This is for enabling SSL/TLS when you use FTP, SMTP, POP3, IMAP etc.
.IP CURLUSESSL_NONE
Don't attempt to use SSL.
.IP CURLUSESSL_TRY
Try using SSL, proceed as normal otherwise.
.IP CURLUSESSL_CONTROL
Require SSL for the control connection or fail with \fICURLE_USE_SSL_FAILED\fP.
.IP CURLUSESSL_ALL
Require SSL for all communication or fail with \fICURLE_USE_SSL_FAILED\fP.
.SH DEFAULT
CURLUSESSL_NONE
.SH PROTOCOLS
FTP, SMTP, POP3, IMAP
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com/dir/file.ext");

  /* require use of SSL for this, or fail */
  curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_ALL);

  /* Perform the request */
  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Added in 7.11.0. This option was known as CURLOPT_FTP_SSL up to 7.16.4, and
the constants were known as CURLFTPSSL_*
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_SSLVERSION "(3), " CURLOPT_PROXY_SSLVERSION "(3), "
.BR CURLOPT_SSL_OPTIONS "(3), "