Преобразовать текстовый адрес хоста в цифровой адрес
#include <sys/socket.h>#include <arpa/inet.h>int inet_pton( int af,const char *src,void *dst );
libc
The inet_pton() function converts the standard text representation of the numeric network address (src) into its numeric network byte-order binary form (dst).
The converted address is stored in network byte order in dst. The buffer pointed to by dst must be large enough to hold the numeric address:
Family | Numeric address size |
---|---|
AF_INET | 4 bytes |
AF_INET6 | 16 bytes |
AF_INET addresses
IPv4 addresses must be specified in the standard dotted-decimal form:
ddd.ddd.ddd.ddd
where ddd is a one- to three-digit decimal number between 0
and 255
.
![]() | Many existing implementations of inet_addr() and inet_aton() accept nonstandard input: octal numbers, hexadecimal numbers, and fewer than four numbers. The inet_pton() function doesn't accept these formats. |
AF_INET6 addresses
IPv6 addresses must be specified in one of the following standard formats:
x:x:x:x:x:x:x:x
where x is a hexadecimal value for one of the eight 16-bit pieces of the address. For example:
DEAD:BEEF:7654:3210:FEDC:3210:7654:BA98
417A:200C:800:8:0:0:0:1080
1080:0:0:0:8:800:200C:417A
FF01:0:0:0:0:0:0:43
0:0:0:0:0:0:0:1
0:0:0:0:0:0:0:0
can be represented as:
1080::8:800:200C:417A
FF01::43
::1
::
A convenient format when dealing with mixed IPv4 and IPv6 environments is:
x:x:x:x:x:x:d.d.d.d
where x is a hexadecimal value for one of the six high-order 16-bit pieces of the address and d is a decimal value for one of the four low-order 8-bit pieces of the address (standard AF_INET representation). For example:
0:0:0:0:0:0:13.1.68.3
0:0:0:0:0:FFFF:129.144.52.38
Or, in their compressed forms:
::13.1.68.3
::FFFF:129.144.52.38
#include <stdio.h>#include <stdlib.h>#include <sys/socket.h>#include <arpa/inet.h>#include <errno.h>#define INADDR "10.1.0.29"#define IN6ADDR "DEAD:BEEF:7654:3210:FEDC:3210:7654:BA98"int main(){struct in_addr inaddr;struct in6_addr in6addr;char buf[INET_ADDRSTRLEN], buf6[INET6_ADDRSTRLEN];int rval;if ( (rval = inet_pton( AF_INET, INADDR, &inaddr )) == 0 ){printf( "Invalid address: %s\n", INADDR );exit( EXIT_FAILURE );} elseif ( rval == -1 ){perror( "inet_pton" );exit( EXIT_FAILURE );}if ( inet_ntop( AF_INET, &inaddr, buf, sizeof( buf ) ) != NULL )printf( "inet addr: %s\n", buf );else {perror( "inet_ntop" );exit( EXIT_FAILURE );}if ( (rval = inet_pton( AF_INET6, IN6ADDR, &in6addr )) == 0 ){printf( "Invalid address: %s\n", IN6ADDR );exit( EXIT_FAILURE );} elseif ( rval == -1 ){perror( "inet_pton" );exit( EXIT_FAILURE );}if ( inet_ntop( AF_INET6, &in6addr, buf6, sizeof( buf6 ) ) != NULL )printf( "inet6 addr: %s\n", buf6 );else {perror( "inet_ntop" );exit( EXIT_FAILURE );}return (EXIT_SUCCESS);}
POSIX 1003.1
Основано на: RFC 2373
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