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POReading std::string from binary file
 

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    <p>I have a couple of functions I created a while ago for reading and writing std::strings to a FILE* opened for reading in binary mode. They have worked fine before (and WriteString() still works) but ReadString() keeps giving me memory corruption errors at run-time. The strings are stored by writing their size as an unsigned int before the string data as char.</p> <pre><code>bool WriteString(std::string t_str, FILE* t_fp) { // Does the file stream exist and is it valid? If not, return false. if (t_fp == NULL) return false; // Create char pointer from string. char* text = const_cast&lt;char*&gt;(t_str.c_str()); // Find the length of the string. unsigned int size = t_str.size(); // Write the string's size to the file. fwrite(&amp;size, sizeof(unsigned int), 1, t_fp); // Followed by the string itself. fwrite(text, 1, size, t_fp); // Everything worked, so return true. return true; } std::string ReadString(FILE* t_fp) { // Does the file stream exist and is it valid? If not, return false. if (t_fp == NULL) return false; // Create new string object to store the retrieved text and to return to the calling function. std::string str; // Create a char pointer for temporary storage. char* text = new char; // UInt for storing the string's size. unsigned int size; // Read the size of the string from the file and store it in size. fread(&amp;size, sizeof(unsigned int), 1, t_fp); // Read [size] number of characters from the string and store them in text. fread(text, 1, size, t_fp); // Store the contents of text in str. str = text; // Resize str to match the size else we get extra cruft (line endings methinks). str.resize(size); // Finally, return the string to the calling function. return str; } </code></pre> <p>Can anyone see any problems with this code or have any alternative suggestions?</p>
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