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Tzgram Struct Reference

Data type for incoming zephyrgrams. More...

List of all members.

Public Attributes
	personal
	Boolean value indicating whether the message is personal. More...
	opcode
	Opcode of the message. More...
	class
	Class of the message. More...
	instance
	Instance within the class of the message. More...
	sender
	Name of the sender of the message. More...
	fromhost
	Host name the message was sent from. More...
	ztime
	Time the message was sent. More...
	auth
	Description of the authenticity of the message. More...
	fields
	Actual data attached to the message. More...
	numfields
	Number of body fields in the message. More...

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Detailed Description

Data type for incoming zephyrgrams.

This structure describes an incoming zephyrgram for processing by later code. Zephyrs are sent to triples of a class, an instance within that class, and a recipient. You can subscribe to any triple, provided that the recipient is either your own user name or null (``*''). Subscribing to an instance of null (again, ``*'' to the command-line clients) subscribes you to all instances of the specified class. Incoming zephyrs will always have a class and an instance; since there are only two useful cases of the recipient (``me'' or ``all users''), incoming messages are classified as personal or not.

Definition at line 90 of file zephyr-core.vtc.

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Member Data Documentation

Tzgram::auth

Description of the authenticity of the message. This is a string value. It can have the value ``yes'' if authentication was enabled for the message and the authenticator matched, ``no'' if authentication was not enabled, or ``forged'' if authentication was enabled but the authenticator on the message was incorrect. Authentication is generally done using Kerberos; this is a reasonably good indicator that the sender actually did send the message. Note that the body of the message and other metadata is never encrypted in the Zephyr system.

Tzgram::class

Class of the message.

Tzgram::fields

Actual data attached to the message. This field contains an array of body fields that make up the text of the message. zwrite by default uses two fields, where the first field is the signature and the second the message body. A zephyr with only one field is presumed to have no signature; zephyrs with more than two fields do not have a predefined meaning. zwgc will display the first field of these messages as signatures.

Tzgram::fromhost

Host name the message was sent from.

Tzgram::instance

Instance within the class of the message.

Tzgram::numfields

Number of body fields in the message. This is just a count of the number of fields in fields.

Tzgram::opcode

Opcode of the message. Most messages will have a null opcode. Some logging code, the zcrypt and kzwrite programs, and jhawk use the opcode to indicate various things. Opcodes are also widely used for internal zephyr messages.

Tzgram::personal

Boolean value indicating whether the message is personal. This variable is 1 if it is personal, meaning that the recipient field pointed at the current user, or 0 otherwise, for a zephyr with a null recipient field (typically written as ``*'').

Tzgram::sender

Name of the sender of the message.

Tzgram::ztime

Time the message was sent. Note that this field is set by the client and neither verified nor modified by the server; thus, it only gives a rough indication of when the message was actually sent.

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The documentation for this struct was generated from the following file:

• zephyr-core.vtc

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