msmtp is an SMTP client. In the default mode, it transmits a mail to an SMTP server (for example at a free mail provider) which does the delivery. To use this program with your mail user agent (MUA), create a configuration file with your mail account(s) and tell your MUA to call msmtp instead of /usr/sbin/sendmail. Features include: - Sendmail compatible interface (command line options and exit codes). - PIPELINING support for increased transmission speed. - DSN (Delivery Status Notification) support. - RMQS (Remote Message Queue Starting) support (ETRN keyword). - IPv6 support. - LMTP support. - Authentication methods PLAIN, LOGIN, and CRAM-MD5. - Support for multiple accounts. Optional features, depending on external libraries: - TLS/SSL support, including client certificates (requires GnuTLS or OpenSSL). - Additional authentication methods EXTERNAL, GSSAPI, SCRAM-SHA-1, DIGEST-MD5, NTLM (requires GNU Libgsasl). - Support for Internationalized Domain Names (IDN) (requires GNU Libidn). - Native language support (NLS) (may require GNU libintl). The homepage of this program is <http://msmtp.sourceforge.net/>. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License (see the file COPYING) as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.