C++ Program in Docker container

Question

I am using following function inside container to execute command line argument cd /mypath && sha1sum -c mysha1sumfile to compare the sha1sum of files available in /mypath with the values in mysha1sumfile in the same path. The command is working in when I execute it as binary. The same is working when I tried manually inside the container by executing /bin/bash (inside container). But not working from the program.

executeCmd(const char* command)
{
  string response = "";
  char buffer[256];   
  FILE* pipe = popen(command,"r");  

  if(!pipe)  {  
    response = "ERROR";  
  }  
  while(!feof(pipe)){        
    if(fgets(buffer,128,pipe) != NULL){
      response += buffer;
    }  
  }  
  pclose(pipe);  
  return response;  
}

Verified that pipe is not NULL and feof(pipe) is also not NULL . But fgets() returning NULL .

What can cause that?

Answer 1

Thank's for your comment. I could resolve the issue. It was due to a missing library libtinfo.so.5 for shell scrip ("sh") inside the container. After the library has been copied to /lib/ inside the container it started working