curl_easy_strerror Couldn't resolve host name

when use libucrl (c++) to code in ubuntu 16.04, then docker it to the centos 8, report this error:

[ERROR] 2023-03-13_13:33:56 line 715 curl_oper.cpp: could not reslove the host name, now execute res_init().
[ INFO] 2023-03-13_13:33:56 line 718 curl_oper.cpp: 222222
* Could not resolve host: ie-dtp-core-shenzhen-xili1-oss.sit.sf-express.com
* Closing connection 1
[ERROR] 2023-03-13_13:33:56 line 724 curl_oper.cpp: perform error ! Couldn't resolve host name

eg: line 724

 

when to slove this problem:

first:  we use  res_init(); it does not work

second:  we use curl opt   CURLOPT_DNS_SERVERS  and CURLOPT_IPRESOLVE; it does not work

 

finally:  we use "ldd" order to see the dependy libs, find two different between os(ubuntu and centos)

both of them are :

1) libcurl.so

2)libresolv.so

we rename the coped libs( 1)and 2) ) from ubuntu, then ues the origin of the centos , the problems solved.