getaddrinfo return -11(EAI_SYSTEM)

getaddrinfo function always return -11(EAI_SYSTEM) even if I typed "google.com" on my embedded linux. But nslookup command works well. The sample code has no problem because it works on Ubuntu. So I think it is linux system's problem. Also I tried to get errno but I noticed getaddrinfo doesn't value to errno. Please help me

This is the sample code

#include <stdio.h>  #include <string.h>  #include <stdlib.h>  #include <netdb.h>  #include <sys/types.h>  #include <sys/socket.h>  #include <arpa/inet.h>    int  lookup_host (const char *host)  {    struct addrinfo hints, *res, *result;    int errcode;    char addrstr[100];    void *ptr;      memset (&hints, 0, sizeof (hints));    hints.ai_family = PF_UNSPEC;    hints.ai_socktype = SOCK_STREAM;    hints.ai_flags |= AI_CANONNAME;      errcode = getaddrinfo (host, NULL, &hints, &result);    if (errcode != 0)      {          fprintf(stderr, "getaddrinfo: %d\n", errcode);        return -1;      }        res = result;      printf ("Host: %s\n", host);    while (res)      {        inet_ntop (res->ai_family, res->ai_addr->sa_data, addrstr, 100);          switch (res->ai_family)          {          case AF_INET:            ptr = &((struct sockaddr_in *) res->ai_addr)->sin_addr;            break;          case AF_INET6:            ptr = &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr;            break;          }        inet_ntop (res->ai_family, ptr, addrstr, 100);        printf ("IPv%d address: %s (%s)\n", res->ai_family == PF_INET6 ? 6 : 4,                addrstr, res->ai_canonname);        res = res->ai_next;      }        freeaddrinfo(result);      return 0;  }    int main (void)  {    char inbuf[256];    int len;    do {      bzero(inbuf, 256);      printf("Type domain name:\n");      fgets(inbuf, 256, stdin);      len = strlen(inbuf);      inbuf[len-1] = '\0';      if(strlen(inbuf) > 0)        lookup_host (inbuf);      else        return EXIT_SUCCESS;    } while(1);  }  

https://stackoverflow.com/questions/66667257/getaddrinfo-return-11eai-system March 17, 2021 at 01:04PM