How to Read File Bytes into a Char Array in C Without getline()?

How to Retrieve File Bytes into a Char Array in C

To read file bytes into a char array without using getline(), consider using ifstream::read(). Follow these steps:

1. Open the File:

   <code class="cpp">std::ifstream infile("C:\MyFile.csv");</code>

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2. Get File Length:

   <code class="cpp">infile.seekg(0, std::ios::end);
   size_t length = infile.tellg();
   infile.seekg(0, std::ios::beg);</code>

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3. Ensure Buffer Size:

   <code class="cpp">if (length > sizeof (buffer)) {
    length = sizeof (buffer);
   }</code>

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4. Read the File:

   <code class="cpp">infile.read(buffer, length);</code>

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Additional Notes:

• Opening the file in binary mode (e.g., with std::ios_base::binary) is recommended for accurate byte handling.
• While seekg() and tellg() are generally reliable, they may not always provide exact file size in some cases.
• For reading the entire file in one operation and handling large files, using std::vector and std::istreambuf_iterator may offer more flexibility.

Updated Approach (2019):

To account for potential errors during reading, consider the following approach:

<code class="cpp">size_t chars_read;

if (!(infile.read(buffer, sizeof(buffer)))) {
    if (!infile.eof()) {
        // Handle error during reading
    }
}

chars_read = infile.gcount(); // Get actual number of bytes read</code>

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