smtpd --- Simple Mail Transfer Protocol daemon
smtpd [-dhnv] [-D macro=value] [-f file] [-P system] [-T trace]
smtpd is a Simple Mail Transfer Protocol (SMTP) daemon which can be used as a machine's primary mail system. smtpd can listen on a network interface and handle SMTP transactions; it can also be fed messages through the standard sendmail(8) interface. It can relay messages through remote mail transfer agents or store them locally using either the mbox or maildir format. This implementation supports SMTP as defined by RFC 5321 as well as several extensions. A running smtpd can be controlled through smtpctl(8). The options are as follows: -D macro=value Define macro to be set to value on the command line. Overrides the definition of macro in the configuration file. -d Do not daemonize. If this option is specified, smtpd will run in the foreground and log to stderr. -f file Specify an alternative configuration file. -h Display version and usage. -n Configtest mode. Only check the configuration file for validity. -P system Pause a specific subsystem at startup. Normal operation can be resumed using smtpctl(8). This option can be used multiple times. The accepted values are: mda Do not schedule local deliveries. mta Do not schedule remote transfers. smtp Do not listen on SMTP sockets. -T trace Enables real-time tracing at startup. Normal operation can be resumed using smtpctl(8). This option can be used multiple times. The accepted values are: * imsg * io * smtp (incoming sessions) * filters * transfer (outgoing sessions) * bounce * scheduler * expand (aliases/virtual/forward expansion) * lookup (user/credentials lookups) * stat * rules (matched by incoming sessions) * mproc * all -v Produce more verbose output.
/etc/mailname Alternate server name to use. /etc/smtpd.conf Default smtpd configuration file. /var/run/smtpd.sock UNIX-domain socket used for communication with smtpctl(8). /var/spool/smtpd/ Spool directories for mail during processing.
smtpd.conf(5), mailwrapper(8), smtpctl(8)
J. Klensin, Simple Mail Transfer Protocol, RFC 5321, October 2008.
The smtpd program first appeared in OpenBSD 4.6.
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.