System() no suitable conversion C++ -

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i have 2 lists file names.

std::list<std::string> userfontlist; std::list<std::string>::iterator it; std::list<std::string> caatfontlist; std::list<std::string>::iterator it2; std::list<std::string> doesnthavelist;

and want compare 2 lists, , delete value matches. every seems fine until add "del /f /q /a" y.c_string(). 

for (it = userfontlist.begin(); !=userfontlist.end(); ++it){     for(it2 = caatfontlist.begin();it2 !=caatfontlist.end();++it2){         if(*it==*it2){             string y = *it;             string k = y.c_str();             string = "del /f /q /a " + k;             system(a);          }     }  }

system(a) says have "no suitable conversion function std string const char * exists". if put whole thing 1 string works, not when concatenate string , y.c_str(). have had no luck trying convert std::string const *char, not sure if helps.

exactly says, there's no version of system() understands std::string , std::string can't freely converted const char * (which system() understand), because std::string may go away in ways don't make sense in general case.

you can explicitly convert std::string const char * easily, though: std::string::c_str, write last line as

system(a.c_str());

be aware returned const char *'s lifetime tied string came from, once goes out of scope, pointer becomes invalid. case fine time use it, though, since system() won't "hold on" pointer past own return.


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