netflex Protocol Specification v1

V1 spec document for a demo protocol I did for a tutorial.

Quality Status: Release

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Netflex has a 3 byte header with an action, option and size. The action determines the instruction the other partner is giving, the option is how they want it done and the size is the size of the payload. The number of payloads varies depending on the type, and before each payload comes the size.

MIN SIZE: 3 bytes
MAX SIZE: 255 bytes

Actions

Action	Description	Byte	Payloads
WATCH	Instruct partner to modify the watch list.	0x00	1
QUIT	Instructs partner the sender is exiting.	0x01	0
NOTIFY	Notify the user since an event just occurred.	0x02	2
REPLY	Acknowledge the previous message, or say it was invalid.	0x03	0
STATUS	Let partner know about application-level status conditions.	0x04	0
UNSET	Permanently reserved as the 'null' value for an action.	0xFF	0

Options

WATCH

Option	Description	Byte
ADD	Add a file to the watch list.	0x00
REM	Remove a file to the watch list.	0x01

QUIT

Option	Description	Byte
USER	User requested to exit the program.	0x00
ERROR	The partner encountered an error and it will quit.	0x01

NOTIFY

Option	Description	Byte
CREATE	A file creation event occurred.	0x00
DELETE	A file deletion event occurred.	0x01
ACCESS	A file access event occurred.	0x02
CLOSE	A file close event occurred.	0x03
MODIFY	A file modification event occurred.	0x04
MOVE	A file move event occurred.	0x05

REPLY

Option	Description	Byte
VALID	Acknowledge a valid message.	0x00
BAD_SIZE	Message exceeded max size or was reported incorrectly.	0x01
BAD_ACTION	Requested action not known.	0x02
BAD_OPTION	Requested option not known.	0x03
BAD_PATH	The path requested to watch could not be found.	0x04
INVALID_DATA	Data outside ASCII alpha-numeric (plus special characters) range.	0x05

STATUS

Option	Description	Byte
SUCCESS	Application-level operation success.	0x00
ERR_INIT_INOTIFY	The partner couldn't initialise an inotify instance.	0x01
ERR_ADD_WATCH	The partner couldn't add a path to inotify.	0x02
ERR_READ_INOTIFY	The partner couldn't read from the inotify instance.	0x03
ERR_RM_WATCH	The partner couldn't remove a path from inotify.	0x04

Examples