fstream just wont create file [closed]

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Hi I'm trying to use a fstream file handle doing following:

• write to file
• read from file
• create file(if not existing)

the problem: For some reason I am not able to make it creating the file.

filepath= name + "/mails.txt";
mkdir(name.c_str(),0600);
log.open(filepath.c_str(), 开发者_JS百科ios::in|ios::out|ios::ate);
if(!log.is_open())cout<<"error"<<endl;
log<<flush;

if the file exists its doing his job but when the file does not exist it wont.

edit: because i badly failed to poste the code in a comment i try it here :D

user::user(string aaa)
{
string filepath;
name=aaa;
filepath= name + "/mails.txt";
mkdir(name.c_str(),0666);


//toch("mails.txt",0600);
log.open(name.c_str(), ios::in|ios::out|ios::ate);
if(!log.is_open()){
    log.close();
    log.open(name.c_str(), ios::in|ios::out|ios::trunc);
}
if(!log.is_open())cout<<"error"<<endl;
log<<flush;
cout<<"message written"<<endl;
}

if there is a system commant like mkdir for creating the .txt it would help too i think

---

Fstream cannot create a file when using the ios::in. It can only open existing files.
What you should do, is first, check if it opens a file. If it does not, close it, clear its state, and open with ios::out - this will create the file.

EDIT:

You can create a file using ios::in if you specify ios::trunc. However, if the file exists, then you will be deleting all its contents.