C#

private FileWatcher_Changed(...)
{
    while(!IsFileAvailable())
    {
      // Do nothing until file is read-write<br />
    }

    // Do other stuff with the file
}

public bool IsFileAvailable(String sFilename)
{
    bool results = false;

    try
    {
        using (var inputStream = File.Open(sFilename, FileMode.Open, FileAccess.Read, FileShare.None))
        {
            results = inputStream.Length > 0;
        }
    }
    catch (Exception)
    {
        results = false;
    }

    return results;
}

if (i != j        // if i is not equal to j
&&                // AND
i % j == 0)       // i divided by j leaves no remeander
// then i cannot be prime

if (i != j && i % j == 0)
    {
    isPrime = false;
    break;
    }