ACTION_HEADER structure (nb30.h)

[Netbios is not supported on Windows Vista, Windows Server 2008, and subsequent versions of the operating system]

The ACTION_HEADER structure contains information about an action. This action is an extension to the standard transport interface.

Syntax

typedef struct _ACTION_HEADER {
  ULONG  transport_id;
  USHORT action_code;
  USHORT reserved;
} ACTION_HEADER, *PACTION_HEADER;

transport_id

Specifies the transport provider. This member can be used to check the validity of the request by the transport.

This member is always a four-character string. All strings starting with the letter M are reserved, as shown in the following example.

Windows XP: Certain legacy networking protocols, including NetBEUI, will no longer be supported.

action_code

Specifies the action.

reserved

Reserved.

The scope of the action is determined by the ncb_lsn and ncb_num members of the NCB structure, as follows.

	ncb_lsn = 0	ncb_lsn != 0
ncb_num = 0	Action applies to control channel associated with the valid LAN adapter.	Action applies to connection identifier associated with the valid local session number.
ncb_num != 0	Action applies to address associated with the valid LAN adapter.	Illegal combination.

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	nb30.h