AIOSMTPD(1)

✨ NAME ✨

Okay bestie, welcome to aiosmtpd(1) 💖 The name is aiosmtpd, an asyncio based SMTP server 🧚

It's an asynchronous, RFC 5321 compliant Simple Mail Transfer Protocol (SMTP) server 💌 and it supports customizable extensions, so you can make it your own 🎀

• Author — The aiosmtpd Developers
• Date — 2025-03-23
• Copyright — 2015-2022, The aiosmtpd Developers
• Version — 1.4.6
• Manual section — 1

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✨ SYNOPSIS ✨

Here's the vibe for how you call it 💅

usage: aiosmtpd [-h] [-v] [-n] [-c CLASSPATH] [-s SIZE] [-u] [-d]
                [-l [[HOST][:PORT]]] [--smtpscert CERTFILE]
                [--smtpskey KEYFILE] [--tlscert CERTFILE] [--tlskey KEYFILE]
                [--no-requiretls]
                [CLASSARGS ...]

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✨ Options ✨

• CLASSARGS — Extra arguments that get passed along to the handler CLASS 🧚
• -h, --help — Shows the help message and exits 🌸
• -v, --version — Shows the program's version number and exits 🦋
• -n, --nosetuid — Normally this program tries to setuid nobody 🙈 but if you set this flag, it won't. The setuid call fails when you're not running as root, so in that case, use this flag 💀
• -c <CLASSPATH>, --class <CLASSPATH> — Picks the handler class for SMTP events, written as a Python dotted import path 💖 That class can process received messages and do other stuff during the SMTP dialog. By default it uses aiosmtpd.handlers.Debugging ✨
• -s <SIZE>, --size <SIZE> — Caps the total size of an incoming message at SIZE bytes using the RFC 1870 SIZE extension 📦 The default is 33,554,432 bytes 👑
• -u, --smtputf8 — Turns on the SMTPUTF8 extension from RFC 6531 🌈
• -d, --debug — Cranks up the debugging output 🔥 Every -d you add bumps the debugging level up by one 📈
• -l <[HOST][:PORT]>, --listen <[HOST][:PORT]> — Optional host and port to listen on 🦋 If you leave out the PORT part, port 8025 is used. If you only give :PORT, the hostname becomes localhost. If you give neither, you get localhost:8025 🍓
• --smtpscert <CERTFILE> — The certificate file for SMTPS 🔐 If you use it, you also have to specify --smtpskey 🫶
• --smtpskey <KEYFILE> — The key file for SMTPS 🔑 If you use it, you also have to specify --smtpscert 🫶
• --tlscert <CERTFILE> — The certificate file for STARTTLS 🔐 If you use it, you also have to specify --tlskey 🫶
• --tlskey <KEYFILE> — The key file for STARTTLS 🔑 If you use it, you also have to specify --tlscert 🫶
• --no-requiretls — Turns off require_starttls on the SMTP class 🙅‍♀️ By default, require_starttls is True. This does nothing if --tlscert and --tlskey aren't specified 💤

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✨ ENVIRONMENT ✨

• AIOSMTPD_CONTROLLER_TIMEOUT — How long the main thread waits (in seconds) for the SMTP thread to be ready ⏰ Default: 1.0

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✨ AUTHOR ✨

The aiosmtpd Developers 🫶

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✨ COPYRIGHT ✨

2015-2022, The aiosmtpd Developers 💜

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That's the whole tea, bestie! ☕ You just read about aiosmtpd 1.4.6, dated 2025-03-23, and you absolutely slayed it 💅🌸