processing command line args

This is a discussion on processing command line args within the C++ Programming forums, part of the General Programming Boards category; Here is my program: Code: int main( int argc, char *argv[] ){ if( argc == 2 ){ cout << "Found ...

  1. #1
    Registered User
    Join Date
    Feb 2008
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    processing command line args

    Here is my program:
    Code:
    int main( int argc, char *argv[] ){
    
        if( argc == 2 ){
    
            cout << "Found an argument." << endl;
    
            cout << argv[1] << endl; // Displays 'auto' to the screen.
    
            if( argv[1] == "auto" ){ // This statement is NOT true...
    
                cout << "Found 'auto' argument." << endl;
            }
        }
    
        return 0;
    }
    The argument is found no problem, but the second if statement is NOT true. Why? Do I need to overload the operator==?

    Help please.

  2. #2
    C++ Witch laserlight's Avatar
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    You can either use strcmp(), or use std::string, e.g.,

    Code:
    if (std::string(argv[1]) == "auto")
    At the moment the code is just comparing pointers, not strings.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

  3. #3
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    Feb 2008
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    2
    Wow. So simple! Thank you.

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