How to Efficiently Read All Bytes from a File into a Character Array in C ?

How to Retrieve All Bytes from a File into a Character Array in C

Given a file located at "C:MyFile.csv" and a character array buffer of size 10,000, how can you efficiently read all the bytes from the file into the buffer?

Consider the following approach, which is generally preferred over using getline() in this scenario:

<code class="cpp">// Open the file in binary mode to preserve byte-by-byte fidelity
std::ifstream infile("C:\MyFile.csv", std::ios_base::binary);

// Determine the file's size
infile.seekg(0, std::ios::end);
size_t file_size = infile.tellg();
infile.seekg(0, std::ios::beg);

// Ensure that the buffer is of sufficient size
if (file_size > sizeof(buffer)) {
    // Handle the case where the file exceeds the buffer's capacity
}

// Read the entire file's contents into the buffer
infile.read(buffer, file_size);

// Obtain the actual number of bytes read from the file
std::streamsize bytes_read = infile.gcount();</code>

Additional Notes:

• Using seekg() and tellg() to determine the file's size is generally reliable but not guaranteed, so consider additional error handling.
• If the file is opened in non-binary mode, some character translations may occur, potentially causing the file_size to differ from the number of bytes ultimately stored in buffer.
• For larger files or cases where you prefer resizable buffers, consider using std::vector and std::istreambuf_iterator for more efficient file reading.

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