getservbyport
The Windows
Sockets getservbyport function gets service information corresponding to
a port and protocol.
struct servent FAR * getservbyport (
|
int port, |
|
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const char
FAR* proto |
|
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); |
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Parameters
port
[in] The port
for a service, in network byte order.
proto
[in] An
optional pointer to a protocol name. If this is NULL, getservbyport
returns the first service entry for which the port matches the s_port.
Otherwise, getservbyport matches both the port and the proto.
Remarks
getservbyport returns a pointer to a servent structure as described
above for getservbyname.
The pointer
which is returned points to a structure which is allocated by Windows Sockets.
The application must never attempt to modify this structure or to free any of
its components. Furthermore, only one copy of this structure is allocated per
thread, and so the application should copy any information which it needs
before issuing any other Windows Sockets function calls.
Return Values
If no error
occurs, getservbyport returns a pointer to the servent structure
described above. Otherwise, it returns a NULL pointer and a specific error
number can be retrieved by calling WSAGetLastError.
Error Codes
|
WSANOTINITIALISED |
A successful
WSAStartup must occur before using this function. |
|
WSAENETDOWN |
The network
subsystem has failed. |
|
WSAHOST_NOT_FOUND |
Authoritative
Answer Service not found. |
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WSATRY_AGAIN |
Non-Authoritative
Service not found, or server failure. |
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WSANO_RECOVERY |
Nonrecoverable
errors, the services database is not accessible. |
|
WSANO_DATA |
Valid name,
no data record of requested type. |
|
WSAEINPROGRESS |
A blocking
Windows Sockets 1.1 call is in progress, or the service provider is still
processing a callback function. |
|
WSAEFAULT |
The proto
argument is not a valid part of the user address space. |
|
WSAEINTR |
The
(blocking) call was canceled through WSACancelBlockingCall. |
See Also