Handshake Messages

Connection establishment and version negotiation. More...

Collaboration diagram for Handshake Messages:

Variables
const char *const	kMsgHello
	Server hello message.
const char *const	kMsgHelloArgs
	Format string for server hello message arguments.
const char *const	kMsgHelloBack
	Client hello response message.
const char *const	kMsgHelloBackArgs
	Format string for client hello response arguments.

Detailed Description

Connection establishment and version negotiation.

Variable Documentation

kMsgHello

const char* const kMsgHello

extern

Server hello message.

Direction: Primary → Secondary Format: "%7s%2i%2i" Parameters:

• $1: Protocol name (7 bytes, fixed-size) - A fixed-size field for the protocol identifier, used for backward compatibility. The supported values are "Synergy" or "Barrier". "Barrier" is the default protocol name, while "Synergy" is used only for backwards compatibility. This is an exception to the standard length-prefixed string format.
• $2: Server major version number (2 bytes)
• $3: Server minor version number (2 bytes)

Example:

Barrier protocol, version 1.8

"Barrier\x00\x01\x00\x08"

This is the first message sent by the server after a client connects. The client uses this to determine protocol compatibility.

See also

kMsgHelloBack

Since

Protocol version 1.0

kMsgHelloArgs

const char* const kMsgHelloArgs

extern

Format string for server hello message arguments.

Format: "%2i%2i" Parameters:

• $1: Server major version number (2 bytes)
• $2: Server minor version number (2 bytes)

Used as part of dynamic hello message construction.

See also

kMsgHello

Since

Protocol version 1.0

kMsgHelloBack

const char* const kMsgHelloBack

extern

Client hello response message.

Direction: Secondary → Primary Format: "%7s%2i%2is" Parameters:

• $1: Protocol name (7 bytes, fixed-size) - A fixed-size field for the protocol identifier, which must match the server's. The supported values are "Synergy" or "Barrier". "Barrier" is the default protocol name, while "Synergy" is used only for backwards compatibility. This is an exception to the standard length-prefixed string format.
• $2: Client major version number (2 bytes)
• $3: Client minor version number (2 bytes)
• $4: Client name (string) - A standard length-prefixed string.

Example:

Barrier protocol, version 1.8, client name "workstation"

"Barrier\x00\x01\x00\x08\x00\x00\x00\x0Bworkstation"

Sent by the client in response to kMsgHello. After this exchange, both sides negotiate to use the minimum supported protocol version.

See also

kMsgHello

Since

Protocol version 1.0

kMsgHelloBackArgs

const char* const kMsgHelloBackArgs

extern

Format string for client hello response arguments.

Format: "%2i%2is" Parameters:

• $1: Client major version number (2 bytes)
• $2: Client minor version number (2 bytes)
• $3: Client name (string)

Used as part of dynamic hello message construction.

See also

kMsgHelloBack

Since

Protocol version 1.0