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c++ - ifstream: how to tell if specified file doesn't exist

I want to open a file for reading. However, in the context of this program, it's OK if the file doesn't exist, I just move on. I want to be able to identify when the error is "file not found" and when the error is otherwise. Otherwise means I need to quit and error.

I don't see an obvious way to do this with fstream.


I can do this with C's open() and perror(). I presumed that there was a fstream way to do this as well.

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EDIT: I've been notified that this does not necessarily indicate a file does not exist, as it may be flagged due to access permissions or other issues as well.

I know I'm extremely late in answering this, but I figured I'd leave a comment anyway for anyone browsing. You can use ifstream's fail indicator to tell if a file exists.

ifstream myFile("filename.txt");
    if(myFile.fail()){
        //File does not exist code here
    }
//otherwise, file exists

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