邮件中的最大行长 [英] Max line length in mail

问题描述

为什么邮件（）的php文档说

行数不应大于70个字符。

Lines should not be larger than 70 characters.

（在部分参数消息下）？

(under the part: parameter message)?

有没有指定邮件行长度的RFC？

Is there an RFC specifying the line length of mails?

这个问题：
PHP邮件和线不应该大于70个字符说

没有那么多客户端不能处理长行

there are not that many clients left that cannot deal with long lines

那么它只是坏的构建客户端/服务器做坏的东西到太长的行，
和70是一个测试值或者是有一个RFC或某些
表示邮件应用程序需要处理70个字符长的行？

So is it just bad build clients/servers that do bad stuff to too long lines, and 70 is a tested value that works well enough, or is there an RFC or something that says that mail-applications need to handle 70 char long lines?

推荐答案

Internet邮件格式 RFC最新的是 5322

2.1.1。线长度限制

2.1.1. Line Length Limits

此标准有两个限制，一行中的
个字符数。每行字符必须不超过998
个字符，并且不得超过78个字符，不包括
CRLF。

There are two limits that this standard places on the number of characters in a line. Each line of characters MUST be no more than 998 characters, and SHOULD be no more than 78 characters, excluding the CRLF.

..

更保守的78字符推荐是为了容纳
，用于显示这些
消息的用户界面的许多实现可能会截断或灾难性包装，每行显示
超过78个字符，尽管这样的
实现不符合本规范的意图
（和[RFC2821]如果他们实际上导致信息丢失）。
再次，尽管这个限制是放在消息上，但是在显示消息的实现上它是
的负担

The more conservative 78 character recommendation is to accommodate the many implementations of user interfaces that display these messages which may truncate, or disastrously wrap, the display of more than 78 characters per line, in spite of the fact that such implementations are non-conformant to the intent of this specification (and that of [RFC2821] if they actually cause information to be lost). Again, even though this limitation is put on messages, it is encumbant upon implementations which display messages

（MIME RFC还指定最多76个字符）

(The MIME RFC also specifies a max of 76 characters)

这篇关于邮件中的最大行长的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！