curl/docs/cmdline-opts/ssl.md

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c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Long: ssl Help: Try enabling TLS Protocols: FTP IMAP POP3 SMTP LDAP Added: 7.20.0 Category: tls Multi: boolean See-also:

• ssl-reqd
• insecure
• ciphers Example:
• --ssl pop3://example.com/ ---

--ssl

Warning: this is considered an insecure option. Consider using --ssl-reqd instead to be sure curl upgrades to a secure connection.

Try to use SSL/TLS for the connection - often referred to as STARTTLS or STLS because of the involved commands. Reverts to a non-secure connection if the server does not support SSL/TLS. See also --ftp-ssl-control and --ssl-reqd for different levels of encryption required.

This option is handled in LDAP (added in 7.81.0). It is fully supported by the OpenLDAP backend and ignored by the generic ldap backend.

Please note that a server may close the connection if the negotiation does not succeed.

This option was formerly known as --ftp-ssl (added in 7.11.0). That option name can still be used but might be removed in a future version.