HP 3000 Manuals HP 3000 Manuals
IPCDEST
Creates a destination descriptor.
Syntax
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| IPCDEST ( socketkind[, location][ ,locationlen], protocol, |
| protoaddr, protolen [ ,flags][ ,opt], destdesc[, result])|
| |
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Parameters
socketkind (input)
32-bit integer, by value. Defines the type of socket. The only type
user processes can create is: 3 = call socket.
location (input)
Character array, by reference. The name of the node (either node or
node.domain.organization) on which the destination socket is to be
created. If this parameter is omitted, the local node is assumed.
locationlen (input)
32-bit integer, by value. The length in bytes of the destination node
name. Zero indicates that no location was given (that is, the node is
local). Maximum (for a fully qualified name) is 50.
protocol (input)
32-bit integer, by value. Defines the Transport Layer protocol to be
used. The protocols currently available to user processes are:
* 2 = X.25 protocol
* 4 = TCP
protoaddr (input).
Byte array, by reference. Protocol relative address (remote address)
with which the socket will be associated. The format of this address,
defined by the protocol, is a 2-byte array (16 bits). Nonprivileged
programs must use addresses in the range 30767 to 32767 decimal (%74057
to %77777). For X.25 access to level 3, this address is included in the
CUD field of an X.25 call packet. (See the discussion of IPCCONNECT for
the parameters providing access to the CUD).
protolen (input)
32-bit integer, by value. The length in bytes of the protocol address.
flags
32 bits, by reference. A bit representation of various options. No
flags are currently defined.
opt
(input)
Record or byte array, by reference. A list of options, with associated
information.
* destination network address (code = 16, length=n, n byte buffer)
(input). (X.25 only.)This option allows a user to bypass the use of
the network directory and associated IP address by specifying the
destination node network address.
The first two bytes of the option data field contain the "protocol"
value of the module. For X.25, the protocol value is 2. The rest of
the option data field is relative to that protocol. For X.25, two
subformats are defined: one for the PVC numbers and one for SVC
addresses. The third and fourth bytes of the data field contain a
format identifier, where 1 indicates a PVC number and 0 indicates a
SVC address. The PVC number is a 4 byte field. For a PVC, the total
length of the option field is 8 bytes.
The SVC field is composed of up to 16 nibbles where the first nibble
is the nibble length of the remaining address. An odd number of
nibbles can be passed since the length indicates the significance of
the remaining field. This implies that the option data length for an
SVC is between 5 and 12 bytes inclusive.
destdesc (output)
32-bit integer, by reference. Destination descriptor. Describes the
location of the named call socket. May be used in subsequent NetIPC
calls to IPCCONNECT.
result (output)
32-bit integer, by reference. The error code returned; zero if no error.
Description
The IPCDEST intrinsic creates a destination descriptor that contains
routing information for sending data to another process.
This intrinsic is option variable. The required parameters are:
socketkind, protocol, protoaddr,protolen, and destdesc.
Condition codes returned by this intrinsic are:
* CCE--Succeeded.
* CCL--Failed.
* CCG--Not returned by this intrinsic.
This intrinsic cannot be called in split stack mode.
Protocol-Specific Considerations
The following table outlines parameters that are specific to the
particular protocol you are accessing.
Table 3-6. EPCDEST Protocol Specific Parameters
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| Parameters | TCP | X.25 |
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| opt | | |
| | | |
| |
| | | |
| 16 | n/a | destination\ network address |
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X.25 Considerations
IPCDEST is used to create a destination descriptor for X.25 direct
access. The protoaddr parameter is only used with switched virtual
circuits (SVCs).
Using the destination network address ( opt 16) to directly specify an
X.25 address of an SVC or a PVC number allows the user to bypass the use
of the network directory and the associated IP address.
Cross-System Considerations For TCP
The following are HP 3000 to HP 1000, HP 3000 to HP 9000, and HP 3000 to
PC programming considerations for this intrinsic.
TCP protocol address - Although the ranges of protocol addresses for each
computer system are different, the recommended range of TCP addresses for
user applications is from 30767 to 32767 decimal (%74057 to %77777).