linux获取网络信息函数

获取IP地址

int sys_getIP(char *ip_addr)

{

char ip_sys[80] =

{“ifconfig eth0 | grep inet | cut -d: -f2 | cut -d’ ’ -f1 > ipaddr.txt”};

FILE *ip_fp = NULL;

int error_sys;

if((error_sys = system(ip_sys)) !=0)

{

fprintf(stderr, “[get_eth] ip_sys : 0x%x\n”, error_sys);

}

if ((ip_fp=fopen(“ipaddr.txt”, “r”)) != NULL)

{

fgets(ip_addr, 39, ip_fp);

}

else

{

perror (“fread”);

return -1;

}

fclose (ip_fp);

unlink(“ipaddr.txt”);

return 0;

}

获取子网掩码

int sys_getMask(char *mask_addr)

{

char ip_sys[80] =

{“ifconfig eth0 | grep Mask | cut -dk -f2 | cut -d: -f2 > /tmp/ipaddr.txt”};

FILE *ip_fp = NULL;

int error_sys;

if((error_sys = system(ip_sys)) !=0)

{

fprintf(stderr, “[get_eth] ip_sys : 0x%x\n”, error_sys);

}

if ((ip_fp=fopen(“/tmp/ipaddr.txt”, “r”)) != NULL)

{

fgets(mask_addr, 39, ip_fp);

}

else

{

perror (“fread”);

return -1;

}

fclose (ip_fp);

unlink(“/tmp/ipaddr.txt”);

return 0;

}

获取网关

int sys_getGW(char *gw_addr)

{

FILE *fp;

char buf[512];

char cmd[128];

char *tmp;

strcpy(cmd, “ip route”);

fp = popen(cmd, “r”);

if(NULL == fp)

{

perror(“popen error”);

return “”;

}

while(fgets(buf, sizeof(buf), fp) != NULL) //stroe output one line!!

{

tmp =buf;

while(*tmp && isspace(*tmp))

++ tmp;

if(strncmp(tmp, “default”, strlen(“default”)) == 0)

break;

}

sscanf(buf,”%*s%*s%s”, gw_addr);

printf(“default gateway:%s\n”, gw_addr);

pclose(fp);

return 0;

}

获取mac地址

int sys_getHW(char *hw_addr)

{

char ip_sys[80] =

{“ifconfig | sed -e ‘/.HWaddr /!d;s///;s/ .//’ > hwaddr.txt”};

FILE *ip_fp = NULL;

int error_sys;

if((error_sys = system(ip_sys)) !=0)

{

fprintf(stderr, “[get_eth] ip_sys : 0x%x\n”, error_sys);

}

if ((ip_fp=fopen(“hwaddr.txt”, “r”)) != NULL)

{

fgets(hw_addr, 39, ip_fp);

}

else

{

perror (“fread”);

return -1;

}

fclose (ip_fp);

unlink(“hwaddr.txt”);

return 0;

}