User`s guide

2: DDCMP DLI Functions
DC 900-1343D 43
2.5.1.4 Stop Link Command
Use the dlWrite function with the pOptArgs.usProtCommand field set to
DLI_PROT_SEND_UNBIND and the pOptArgs.usICPCommand field set to
DLI_ICP_CMD_UNBIND to stop a link without ending your session with Freeway. This
command shuts down the link transmitter and receiver. A Stop Link command can be
sent to a link that is active or already inactive. If the
pOptArgs.iProtModifier field is set
to zero (0), then a Stop Link command causes the DTR modem control signal to be
dropped. Otherwise, the DTR modem signal is not dropped.
A
dlRead response (the pOptArgs.usProtCommand field is set to DLI_PROT_SEND_UNBIND
by the DLI) is sent to the client to acknowledge ICP receipt of the Stop Link command.
The
pOptArgs.iProtModifier field is set to “Final Acknowledge of Stop Link” as
described in Section 2.6.1.4 on page 50.
A call to
dlClose (described in the Freeway Data Link Interface Reference Guide) also
stops the link, but terminates the session as well. This is the normal method to termi-
nate a session at the end of a client application. The Stop Link command is useful for
temporarily stopping the link without terminating the session (for example, to recon-
figure the link using the Configure Link command). The link is restarted by issuing a
Start Link command.