Linux中ip地址结构和ip地址的转换

 ip地址结构

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struct sockaddr_in {     sa_family_t    sin_family; /* address family: AF_INET */     in_port_t      sin_port;   /* port in network byte order */     struct in_addr sin_addr;   /* internet address */ };   /* Internet address. */ struct in_addr {     uint32_t       s_addr;     /* address in network byte order */ };

点分十进制ip转换：

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#include <stdio.h> #include <string.h> #include <sys/socket.h> #include <netinet/in.h> #include <netinet/ip.h> #include <arpa/inet.h>   int main() {     const char *ip_str = "192.168.1.1";     //const char *ip_str = "255.255.255.255";     //const char *ip_str = "0.0.0.0";     struct in_addr in;     memset(&in, 0, sizeof(struct in_addr));     in.s_addr = inet_addr(ip_str);        printf("ip addr is:%u\n", in.s_addr);     printf("ip addr is:%s\n", inet_ntoa(in));     memset(&in, 0, sizeof(struct in_addr));     inet_aton(ip_str, &in);     printf("ip addr is:%s\n", inet_ntoa(in));     return 0; }

结果：

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shelmean:[~]$ ./a.out ip addr is:16885952 ip addr is:192.168.1.1 ip addr is:192.168.1.1