How do I know that the end of file has been reached while reading an encrypted file?

Question

C++ / C#

Hello.
The Vigenère cipher is implemented, it is with reading the encrypted file that the problem arises.
The file is read and written using fstream.
The problem is that when I read the encrypted file, I only get two lines, after which it apparently returns EOF.
Tell me how to read the encrypted file to the very end.

Encrypted file content

Ciphertext

[*55
C*?35D��}<G��C?45C*@�5!D�@��D�@�5'�<,F:��?16�C?(5!�<!F#�C(?35�v?5'�=�F9*<!F�D���5C!?*6��<!F#9,<,G�D�G�91< F#:�yF9(�?35�=�F91<$F�C?46�D��G�:�<-G�91<,FsC�F"9(�@�[email protected]�91=�G�9)<'G�C?+5 �< F#:�yF�:�=�G�92<F �C'?.�:�?(�:�<-G�9*�@��:�<!F#9+<+�5D�?&5C*?2�[email protected]'@�9.<'�6�[email protected]���C&?45C*�G�:��?35C)?&5C$?*5!D�@�sC�G�9#<&F9(�?35�<!F90=��6�C!?'6��<)G�:�<"F#9/�yF�91<"F9#�?25C)@�90<F$:�<G�90<-�6�D��F#9$<'F9+=�G�}v?5C&?45"�<&F:�<*G�9&<-F�D��F91=�F:�=�G�D�?(5'C!?/�[email protected]�5'[email protected]�:�=�F:�<G�:��?55'C#?46�C*?2�:�<,F9)<$F":�<$�o9<!F#9,�?)6�[email protected]��9/<,F�C ?45D�[email protected]�5C'?.�9/<'F 9(<(�o9<-F�[email protected]�5!C?45C*@��K���G�9(=�F"9+=��6�C?45!D�F9%<'F9(<,G�9(�y�5��=�F91<$F�[email protected]�5C"?*5�<.F#90=�G�90<-�5%C)?+�91<#F"91�yF:��?16�C?.6�D��F:�=�G�9+=���K���G�C*@�5$C!?5�9'<F90<-�o�����������������������������o��������䢅������Ք���މ�����Γ���ʉ���o���ݖ��������������ҏ���ی���Γ������Ѯ��ؓ����ݓ����ԓ�ݖ���ћ����ڏ��������s�ُ�ˉ�����ϟ���щ�����ݟ���׉������Ѯ���������ԏ���،���ݓ���ԉ�����������Ю��ד���҉�����K�������������������ד���Ө}���ҏ��������U��ى�ڏ�ʕ��ޖ���������Ӏ������ʉ���������ˉ���ޅ������ݓ���Ө}v���ݓ����ݓ�ޖ���ڏ�����Ֆ������ٕ}���ى�ߏ�ԉ����ɉ���������ʉ�ۏ������ۑs������؏�މ�������ז������Չ���������s��������Ӗ����ۅ�����Ӊ�ҏ����я����y���瘏���ؘ����،�䑉�����ꌸ�����������ɤ}����Γ���ى��ݖ��،���ޓ�����瘏��͓���҉����ɗ}vy

Tried in similar ways, getline doesn't return anything after the second line:

geline try

ifstream inf(inputFilename, ios::in);
    while (inf.eof() != false)
    {
      getline(inf, count);
      fileData += count + '\n';
    }
    inf.close();

memblock reads the entire file, but it can't be decrypted

memblock

ifstream inf(inputFilename, ios::in | ios::binary | ios::ate);
    inf.seekg(0, ios::end);
    int length = inf.tellg(); // Длина текста в файле
    inf.seekg(0);

    char* memblock = new char[length];
    inf.read(memblock, length);
    inf.close();

Answer 1

getline encounters the character EOT (0x04, End Of Text) and ends reading.
With such files it is necessary to work in a binary mode. And do not insert line breaks in them, because you will not distinguish them from characters that have become \r (0x0D) and \n (0x0A) in encoded form.