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Windows Sockets 2
Winsock Reference
Winsock Functions
 ntohl Function
ntohl Function

The ntohl function converts a u_long from TCP/IP network order to host byte order (which is little-endian on Intel processors).

Syntax

C++
u_long WSAAPI ntohl(
  __in  u_long netlong
);

Parameters

netlong [in]

A 32-bit number in TCP/IP network byte order.

Return Value

The ntohl function returns the value supplied in the netlong parameter with the byte order reversed. If netlong is already in host byte order, then this function will reverse it. It is up to the application to determine if the byte order must be reversed.

Remarks

The ntohl function takes a 32-bit number in TCP/IP network byte order (the AF_INET or AF_INET6 address family) and returns a 32-bit number in host byte order.

The ntohl function can be used to convert an IPv4 address in network byte order to the IPv4 address in host byte order. This function does not do any checking to determine if the netlong parameter is a valid IPv4 address.

The ntohl function does not require that the Winsock DLL has previously been loaded with a successful call to the WSAStartup function.

Requirements

Minimum supported clientWindows 2000 Professional
Minimum supported serverWindows 2000 Server
HeaderWinsock2.h
LibraryWs2_32.lib
DLLWs2_32.dll

See Also

Winsock Reference
Winsock Functions
htonl
htons
inet_addr
inet_ntoa
InetNtop
ntohs
WSAHtonl
WSAHtons
WSANtohl
WSANtohs

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Build date: 11/12/2009

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