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Obtains a destination descriptor for a named call socket.
Use with TCP access only. Syntax | |
IPCLOOKUP (socketname,nlen[,location][,loclen][,flags],destdesc
[,protocol][,socketkind][,result]) |
- socketname (input)
Character array, by reference. The
name of the socket. - nlen (input)
32-bit integer, by value. The
length in bytes of the specified socket name. Maximum is 16. - location (input)
Character array, by reference. An
environment ID or node name indicating where the socket registry search
is to take place. The domain and organization names which fully
qualify the node/environment designation are optional. If no location
is specified, the local socket registry is searched. This parameter
can be a maximum of 50 characters long. - loclen (input)
32-bit integer, by value. The
length in bytes of the location parameter. A zero value indicates
that the socket registry search is to take place on the local node. - flags (input)
32 bits, by reference. A
bit representation of various options. The only flag defined is:
flags [0]. It causes the destination descriptor to be "protected." A
protected destination descriptor is one which only privileged users
may create or use. - destdesc (output)
32-bit integer, by reference. The
returned destination descriptor, which the calling process may use
to access the named socket as a destination. This descriptor is
required by the IPCCONNECT intrinsic. - protocol (output)
32-bit integer, by reference. A
number identifying the protocol module with which the socket is
associated: The only protocol available to user processes is: 4
= TCP. - socketkind (output)
32-bit integer, by reference. A
number which identifies the socket's type: 3 = call. - result (output)
32-bit integer, by reference. The
error code returned; zero if no error.
The IPCLOOKUP intrinsic is used to gain access to a named socket.
When supplied with the socket's name, it returns a destination
descriptor that the calling process can use in order to connect
to and send messages to that socket. It is important to synchronize
the naming and lookup of sockets so that the naming occurs before
the lookup. If these two events are occurring concurrently, you
can repeat the IPCLOOKUP call, checking the result parameter after each
call, until the call is successful. If the result value is 37 ("NAME
NOT FOUND"), the socket has not yet been given the name.
The following Pascal program fragment illustrates this idea: socketname := 'RAINBOW';
location := 'SOMEWHERE';
result := 0;
repeat
IPCLOOKUP (socketname, 7, location, 9, ,
destdesc, , , result);
until result<>37;
if result<>0 then ERRORPROCEDURE; |
The only required parameters in the IPCLOOKUP intrinsic are socketname, nlen, and destdesc. This intrinsic is option variable. Condition codes
returned by this intrinsic are: CCG — Not returned by this intrinsic.
This intrinsic cannot be called in split stack mode. |
