RESET REQUEST/INDICATION Packet

A process sends a RESET REQUEST packet to reset a VC. The subsystem sends a RESET REQUEST when a close() or shutdown() system call is issued on a PVC.

Figure A-7 RESET REQUEST Packet

The access to the fields in the RESET REQUEST/INDICATION packet is described below:

General Format Identifier

Indicates the packet sequence count (modulo 8 or modulo 128). This field cannot be read or written by an X.25 application.

Logical Channel Identifier

Contains the logical channel identifier. It is controlled by the X.25 subsystem. It can be read with the ioctl(X25_RD_LCI) after the call has been estab lished.

Packet Type Identifier

Indicates the kind of packet. It cannot be read or written directly, but through system calls, the transmission and arrival can be effected.

To read this field on an incoming packet:recv(MSG_OOB) returns a buffer the second byte of which (buf[1]) con tains an indication that a RESET INDICATION packet has arrived (OOB_VC_RESET).

To write this field on an outgoing packet:Use the ioctl(X25_RESET_VC) to transmit a reset packet.

Resetting Cause Code

Indicates the cause code for the RESET REQUEST/INDICATION packet.

To read this field on an incoming packet:recv(MSG_OOB) returns a buffer the second byte of which (buf[2]) con tains the resetting cause field.

To write this field on an outgoing packet:Use the ioctl(X25_WR_CAUSE_DIAG) before the ioctl(X25_RESET_VC) is issued.

Diagnostic Code

Contains the diagnostic code for the RESET REQUEST/INDICATION packet.

To read this field on an incoming packet:recv(MSG_OOB) returns a buffer the second byte of which (buf[3]) con tains the resetting diagnostic code field.

To write this field on an outgoing packet:Use the ioctl(X25_WR_CAUSE_DIAG) before issuing the ioctl(X25_RESET_VC).