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28 .\" From: @(#)inet.3 8.1 (Berkeley) 6/4/93
44 .Nd Internet address manipulation routines
53 .Fn inet_aton "const char *cp" "struct in_addr *pin"
55 .Fn inet_addr "const char *cp"
57 .Fn inet_network "const char *cp"
59 .Fn inet_ntoa "struct in_addr in"
62 .Fa "struct in_addr in"
69 .Fa "const void * restrict src"
70 .Fa "char * restrict dst"
74 .Fn inet_pton "int af" "const char * restrict src" "void * restrict dst"
76 .Fn inet_makeaddr "in_addr_t net" "in_addr_t lna"
78 .Fn inet_lnaof "struct in_addr in"
80 .Fn inet_netof "struct in_addr in"
87 interpret character strings representing
88 numbers expressed in the Internet standard
94 function converts a presentation format address (that is, printable form
95 as held in a character string) to network format (usually a
97 or some other internal binary representation, in network byte order).
98 It returns 1 if the address was valid for the specified address family, or
99 0 if the address was not parseable in the specified address family, or -1
100 if some system error occurred (in which case
103 This function is presently valid for
110 routine interprets the specified character string as an Internet address,
111 placing the address into the structure provided.
112 It returns 1 if the string was successfully interpreted,
113 or 0 if the string is invalid.
118 functions return numbers suitable for use
119 as Internet addresses and Internet network
120 numbers, respectively.
129 or some other binary form, in network byte order) to presentation format
130 (suitable for external display purposes).
133 argument specifies the size, in bytes, of the buffer
138 define the maximum size required to convert an address of the respective
140 It returns NULL if a system error occurs (in which case,
142 will have been set), or it returns a pointer to the destination string.
143 This function is presently valid for
150 takes an Internet address and returns an
152 string representing the address in
157 is the reentrant version of
159 The deprecated routine
161 takes an Internet network number and a local
162 host address on that network, and constructs an Internet address
164 It should only be assumed to work for historical class A/B/C networks.
165 The deprecated routines
169 break apart Internet host addresses, returning
170 the network number and local host address part,
172 assuming the historical class A/B/C network masks.
174 All Internet addresses are returned in network
175 order (bytes ordered from left to right).
176 All network numbers and local address parts are
177 returned as machine byte order integer values.
178 .Sh INTERNET ADDRESSES
179 Values specified using the
182 of the following forms:
183 .Bd -literal -offset indent
190 When four parts are specified, each is interpreted
191 as a byte of data and assigned, from left to right,
192 to the four bytes of an Internet address.
194 When a three part address is specified, the last
195 part is interpreted as a 16-bit quantity and placed
196 in the least significant two bytes of the network address.
198 When a two part address is supplied, the last part
199 is interpreted as a 24-bit quantity and placed in
200 the least significant three bytes of the network address.
202 When only one part is given, the value is stored
203 directly in the network address without any byte
206 All numbers supplied as
211 may be decimal, octal, or hexadecimal, as specified
212 in the C language (i.e., a leading 0x or 0X implies
213 hexadecimal; otherwise, a leading 0 implies octal;
214 otherwise, the number is interpreted as decimal).
222 for malformed requests.
230 was not large enough to store the presentation form of the address.
231 .It Bq Er EAFNOSUPPORT
242 .Xr gethostbyname 3 ,
252 .%T "IP Version 6 Addressing Architecture"
263 does not accept 1-, 2-, or 3-part dotted addresses; all four parts
264 must be specified and are interpreted only as decimal values.
265 This is a narrower input set than that accepted by
269 functions appeared in
274 (0xffffffff) is a valid broadcast address, but
276 cannot return that value without indicating failure.
279 function does not share this problem.
280 The problem of host byte ordering versus network byte ordering is
282 The string returned by
284 resides in a static memory area.
288 function should return a