RtlIpv4StringToAddress (Compact 7)
3/12/2014
This function converts a string representation of an IPv4 address to a binary IPv4 address.
Syntax
LONG NTAPI RtlIpv4StringToAddress(
__in PCTSTR S,
__in BOOLEAN Strict,
__out LPTSTR* Terminator,
__out IN_ADDR* Addr
);
Parameters
- S
A pointer to a buffer that contains the NULL-terminated string representation of the IPv4 address.
- Strict
A value that indicates whether the string must be an IPv4 address represented in strict four-part dotted-decimal notation. If this parameter is TRUE, the string must be dotted-decimal with four parts. If this parameter is FALSE, any of four possible forms are allowed, with decimal, octal, or hexadecimal notation. See the Remarks section for more information.
- Terminator
A parameter that receives a pointer to the character that terminated the converted string. This can be used by the caller to extract more information from the string.
- Addr
A pointer where the binary representation of the IPv4 address is to be stored.
Return Value
| Return code | Description |
|---|---|
NO_ERROR |
The function succeeds. |
ERROR_INVALID_PARAMETER |
An invalid parameter was passed to the function. This error is returned if the Strict parameter was set to TRUE, but the string that is passed in the S parameter did not contain a four-part dotted decimal string representation of an IPv4 address. |
Other |
Use FormatMessage to obtain the message string for the returned error. |
Remarks
The RtlIpv4StringToAddress function is used to convert a string representation of the IPv4 address to an IPv4 address returned in network order (bytes ordered from left to right).
RtlIpv4StringToAddress is a convenience function that does not require that the Windows Sockets DLL be loaded to access a function that is provided in Windows Sockets to perform string to IP address conversion.
If the Strict parameter is set to TRUE, the string pointed to by the S parameter must be in strict dotted-decimal notation. This strict format requires that four parts are specified. Each part is interpreted as a decimal byte of data and assigned, from left to right, to the four bytes of an IPv4 address.
When the Strict parameter is set to FALSE, the string pointed to by S parameter may be in any of the several possible formats. When the buffer pointed to by S parameter contains a three-part address string, the last part is interpreted as a 16-bit quantity and placed in the right side most two bytes of the network address. This makes the three-part address format convenient for specifying Class B network addresses as "128.net.host". When the buffer pointed to by S parameter contains a two-part address string, the last part is interpreted as a 24-bit quantity and placed in the right side most three bytes of the network address. This makes the two part address format convenient for specifying Class A network addresses as "net.host". When the buffer pointed to by S parameter contains only a one-part address string, the value is stored directly in the network address without any byte rearrangement.
On success, the Terminator parameter points to the character that terminated the string that was converted. This allows an application to pass a string that contains an IP address plus additional information to the RtlIpv4StringToAddress function and then parse the remaining information.
When UNICODE or _UNICODE is defined, RtlIpv4StringToAddress is defined to RtlIpv4StringToAddressW, the Unicode version of this function. The string parameters are defined to the PCWSTR data type.
When UNICODE or _UNICODE is not defined, RtlIpv4StringToAddress is defined to RtlIpv4StringToAddressA, the ANSI version of this function. The string parameters are of the PCSTR data type.
The IN_ADDR structure is defined in the Inaddr.h header file.
See Also
Reference
IP Helper Functions
RtlIpv4AddressToString
RtlIpv4AddressToStringEx
RtlIpv4StringToAddressEx
RtlIpv6AddressToString
RtlIpv6AddressToStringEx
RtlIpv6StringToAddress
RtlIpv6StringToAddressEx