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Thread: string to char*?

  1. #1
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    Default string to char*?

    hello everyone,
    this is a rather newbie question, but strings confuse me way too often.

    i have a readFromTextFile() function
    in which i read in a string array lines of text. string lines[6].
    now i want to save each string to a char * variable.
    i guess i will have to do malloc for each char* variable but then?
    should i memcpy? strcpy? or am i completely of course here?
    what should i do?
    thank you for your help.
    nass

  2. #2
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    Default Re: string to char*?

    Quote Originally Posted by nass View Post
    i guess i will have to do malloc for each char* variable but then?
    should i memcpy? strcpy?
    memcpy() and strcpy() are almost the same, but since you are dealing with strings, you should use strcpy() or strncpy().

    There are also strdup() and strndup() which work like malloc()+strcpy().

  3. #3
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    Default Re: string to char*?

    thank you for the quick reply.
    but is it 'legal' in c++ terms to cast

    (char*)&lines[1], in order to use it as source pointer in strcpy?

  4. #4
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    Default Re: string to char*?

    Quote Originally Posted by nass View Post
    but is it 'legal' in c++ terms to cast

    (char*)&lines[1], in order to use it as source pointer in strcpy?
    No, you have to use string::c_str() to get a const char *.

    http://www.cppreference.com/cppstring/c_str.html

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