使用uname()得到主机名

使用uname()得到主机名
struct utsname{
 char sysname[_UTS_NAMESIZE];  /* name of this operating system */
 char nodename[_UTS_NODESIZE]; /* name of this node */
 char release[_UTS_NAMESIZE];  /* O.S release level */
 char version[_UTS_NAMESIZE];  /* O.S version level */
 char machine[_UTS_NAMESIZE];  /* hardware type */
};

#include <sys/utsname.h>
#include <netdb.h>
#include <sys/socket.h>

int main(int argc, char **argv)
{
 struct hostent *hptr;
 struct utsname myname;
 char **pptr;
 char str[32];
 
 if(uname(&myname)<0)
 {
  printf("uname calling error\n");
  return 1;
 }
 printf("localhost name:%s\n",myname.nodename);
 if( (hptr = gethostbyname(myname.nodename)) == NULL)
 {
  printf("gethostbyname calling error\n");
  return 1;
 }
 pptr=hptr->h_addr_list;
 for(;*pptr!=NULL;pptr++)
  printf("  address:%s\n", inet_ntop(hptr->h_addrtype, *pptr, str, sizeof(str)));
 
 return 0;
}