NetIPC 3000/XL Programmer's Reference Manual (5958-8600)

Chapter 3 107
NetIPC Intrinsics
IPCRECVCN
IPCRECVCN
Receives a connection request on a call socket.
Syntax
IPCRECVCN ( calldesc , vcdesc [, flags ][, opt ][, result ])
Parameters
calldesc (input)
32-bit integer, by value. Call socket descriptor. The
socket descriptor for a call socket belonging to this
process.
vcdesc (output)
32-bit integer, by reference. The returned VC socket
descriptor, a number identifying a VC socket belonging
to this process through which data can be sent or
received. This descriptor can be used in other intrinsics.
flags (input)
32 bits, by reference. A bit representation of various
options. The following flags are defined:
• flags [0] — protected (input). (TCP only.) Ensures
that the connection will be “protected” (privileged
users only).
• flags [18] — defer (input). Causes the reply to the
connection request to be deferred. The intrinsic will
complete when a connection request is received, but
the virtual circuit will not be established. The
IPCCONTROL intrinsic can be used later to accept or
reject the connection.
• flags [21] — checksum (input). (TCP only.) Enables
checksum on the Transmission Control Protocol
(TCP) connection for error checking. Checksum may
also be set by the corresponding IPCCONNECT call. If
either side specifies “checksum enabled” then the
connection will be checksummed. TCP checksum
may be enabled globally, over all connections, when
configuring the Network Transport. See the
NS 3000/XL NMMGR Screens Reference Manual for
details on Network Transport configuration.