---
name: "Sisimai::RFC1123"
section: "3pm"
platform: "linux"
package: "libsisimai-perl"
version: "5.3.0-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Sisimai::RFC1123"
---

# Sisimai::RFC1123(3pm)

Internet hostname related class

## NAME

Sisimai::RFC1123 - Internet hostname related class

## SYNOPSIS

```
    use Sisimai::RFC1123;
    print Sisimai::RFC1123->is_internethost("mx2.example.jp"); # 1
    print Sisimai::RFC1123->is_internethost("localhost");      # 0
```

## DESCRIPTION

`"Sisimai::RFC1123"` is a class related to the Internet hosts

## CLASS METHODS

### "is\_internethost(String)"

`is_internethost()` method returns true when the argument is a valid hostname

```
    print Sisimai::RFC1123->is_internethost("mx2.example.jp"); # 1
    print Sisimai::RFC1123->is_internethost("localhost");      # 0
```

## AUTHOR

azumakuniyuki

## COPYRIGHT

Copyright (C) 2024 azumakuniyuki, All rights reserved.

## LICENSE

This software is distributed under The BSD 2-Clause License.