Convert string with explicit escape sequence into relative character

Question

I need a function to convert \"explicit\" escape sequences into the relative non-printable character. Es:

char str[] = \"\\\\n\";
cout << \"Line1\" <         


        

Answer 1

Here's a cute way to do it on Unixy platforms.

It calls the operating system's echo command to make the conversion.

string convert_escapes( string input )
   {
   string buffer(input.size()+1,0);
   string cmd = "/usr/bin/env echo -ne \""+input+"\"";
   FILE * f = popen(cmd.c_str(),"r"); assert(f);
   buffer.resize(fread(&buffer[0],1,buffer.size()-1,f));
   fclose(f);
   return buffer;
   }