Sisima...nknown(3pm)

✨ NAME ✨

okay so bestie, welcome to Sisima...nknown(3pm) — she's a Perl module and her whole name is Sisimai::Reason::HostUnknown, and her entire job? figuring out whether a bounce reason is hostunknown or not 💅 no cap.

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🌸 SYNOPSIS 🌸

literally just this, it's giving minimal:

use Sisimai::Reason::HostUnknown;
print Sisimai::Reason::HostUnknown->match('550 5.2.1 Host Unknown');   # 1

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🦋 DESCRIPTION 🦋

Sisimai::Reason::HostUnknown does a vibe check on whether the bounce reason is hostunknown or not. periodt. and heads up — this class is called only by the Sisimai::Reason class, so she's not out here taking walk-ins, iykyk.

so what even is this error? it's when the domain part of the recipient's email address — aka the right hand side of the @ sign — does not exist 😭. in many cases the domain part is just misspelled, or the domain name has been expired. classic. it's giving typo energy.

Sisimai will set hostunknown to the reason of the email bounce if the value of the Status: field in a bounce mail is 5.1.2. the receipts look like this:

Your message to the following recipients cannot be delivered:

<kijitora@example.cat>:
<<< No such domain.

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👑 CLASS METHODS 👑

text()

text() method returns the fixed string hostunknown. that's it. she said consistency. 💖

print Sisimai::Reason::HostUnknown->text;  # hostunknown

match(string)

match() method returns 1 if the argument matched with patterns defined in this class. match made in heaven fr fr ✨

print Sisimai::Reason::HostUnknown->match('550 5.2.1 Host Unknown');   # 1

true(Sisimai::Fact)

true() method returns 1 if the bounce reason is hostunknown. the argument must be a Sisimai::Fact object — no substitutions, bestie — and this method is called only from the Sisimai::Reason class.

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🎀 AUTHOR 🎀

azumakuniyuki — the icon, the moment, the main character 👑

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🌈 COPYRIGHT 🌈

Copyright (C) 2014-2018,2020,2021,2023-2026 azumakuniyuki, All rights reserved.

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📜 LICENSE 📜

This software is distributed under The BSD 2-Clause License. slay, legally speaking 💜

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okay and for the cute sign-off: this lil page is documented for perl v5.40.1, dated 2026-07-05, and it lives in the User Contributed Perl Documentation section. read it, love it, ship it 🫶💖