RtlIpv4AddressToStringExA function (ip2string.h)
The RtlIpv4AddressToStringEx function converts an IPv4 address and port number to a string in Internet standard format.
Syntax
NTSYSAPI NTSTATUS RtlIpv4AddressToStringExA(
[in] const in_addr *Address,
[in] USHORT Port,
[out] PSTR AddressString,
[in, out] PULONG AddressStringLength
);
Parameters
[in] Address
The IPv4 address in network byte order.
[in] Port
The port number in network byte order format. This parameter is optional.
[out] AddressString
A pointer to the buffer to receive the NULL-terminated string representation of the IPv4 address and port. This buffer should be large enough to hold at least INET_ADDRSTRLEN characters. The INET_ADDRSTRLEN value is defined in the Ws2ipdef.h header file.
[in, out] AddressStringLength
On input, the number of characters that fit in the buffer pointed to by the AddressString parameter, including the NULL terminator.
On output, this parameter contains the number of characters actually written to the buffer pointed to by the AddressString parameter.
Return value
If the function succeeds, the return value is STATUS_SUCCESS.
If the function fails, the return value is one of the following error codes.
| Return code | Description |
|---|---|
|
An invalid parameter was passed to the function. This error is returned if a NULL pointer is passed in the AddressString or AddressStringLength parameter. This error is also returned if the length of the buffer pointed to by the AddressString parameter is not large enough to receive the string representation of the IPv4 address and port. |
|
Use FormatMessage to obtain the message string for the returned error. |
Remarks
The RtlIpv4AddressToStringEx function is used to convert an IPv4 address and port number to the string representation of the IPv4 address in Internet dotted-decimal format followed by a colon character and a string representation of the port.
RtlIpv4AddressToStringEx is a convenience function that does not require that the Windows Sockets DLL be loaded to access a function provided in Windows Sockets to perform IP address to string conversion.
If the length of the buffer pointed to by the AddressString parameter is not large enough to receive the string representation of the IPv4 address and port, RtlIpv4AddressToStringEx returns ERROR_INVALID_PARAMETER and sets the AddressStringLength parameter to the buffer length required.
When either UNICODE or _UNICODE is defined, RtlIpv4AddressToStringEx is defined to RtlIpv4AddressToStringExW, the Unicode version of this function. The AddressString parameter is defined to the PWSTR data type.
When both UNICODE and _UNICODE are not defined, RtlIpv4AddressToStringEx is defined to RtlIpv4AddressToStringExA, the ANSI version of this function. The AddressString parameter is defined to the PSTR data type.
The IN_ADDR structure is defined in the Inaddr.h header file.
An import library containing the RtlIpv4AddressToStringEx function is not included in the Microsoft Windows Software Development Kit (SDK) released for Windows Vista. The RtlIpv4AddressToStringEx function is included in the Ntdll.lib import library included in the Windows Driver Kit (WDK). An application could also use the GetModuleHandle and GetProcAddress functions to retrieve the function pointer from the Ntdll.dll and call this function.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps | UWP apps] |
| Minimum supported server | Windows Server 2008 [desktop apps | UWP apps] |
| Target Platform | Windows |
| Header | ip2string.h (include Mstcpip.h) |
| DLL | Ntdll.dll |
See also
GetModuleHandle
GetProcAddress
InetNtop
InetPton
LoadLibrary
RtlIpv4AddressToString
RtlIpv4StringToAddress
RtlIpv4StringToAddressEx
RtlIpv6AddressToString
RtlIpv6AddressToStringEx
RtlIpv6StringToAddress
RtlIpv6StringToAddressEx
inet_addr
inet_ntoa