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The routines and interpret character strings representing
numbers expressed in the Internet standard notation. The routine interprets
the specified character string as an Internet address, placing the address
into the structure provided. It returns 1 if the string was successfully
interpreted, or 0 if the string is invalid. The and functions return numbers
suitable for use as Internet addresses and Internet network numbers, respectively.
The routine takes an Internet address and returns an string representing
the address in notation. The routine takes an Internet network number
and a local network address and constructs an Internet address from it.
The routines and break apart Internet host addresses, returning the
network number and local network address part, respectively. All Internet
addresses are returned in network order (bytes ordered from left to right).
All network numbers and local address parts are returned as machine format
integer values.
Values specified using the notation take
one of the following forms: a.b.c.d a.b.c a.b a When four parts are specified,
each is interpreted as a byte of data and assigned, from left to right,
to the four bytes of an Internet address. Note that when an Internet address
is viewed as a 32-bit integer quantity on the the bytes referred to above
appear as That is, bytes are ordered from right to left. When a three
part address is specified, the last part is interpreted as a 16-bit quantity
and placed in the right-most two bytes of the network address. This makes
the three part address format convenient for specifying Class B network
addresses as When a two part address is supplied, the last part is interpreted
as a 24-bit quantity and placed in the right most three bytes of the network
address. This makes the two part address format convenient for specifying
Class A network addresses as When only one part is given, the value is
stored directly in the network address without any byte rearrangement.
All numbers supplied as in a notation may be decimal, octal, or hexadecimal,
as specified in the C language (i.e., a leading 0x or 0X implies hexadecimal;
otherwise, a leading 0 implies octal; otherwise, the number is interpreted
as decimal).
The constant is returned by and for malformed
requests.
These functions appeared in
The value
(0xffffffff) is a valid broadcast address, but cannot return that value
without indicating failure. The newer function does not share this problem.
The problem of host byte ordering versus network byte ordering is confusing.
The string returned by resides in a static memory area. Inet_addr should
return a
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