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How do I inform Windows that I'm writing a binary file?

devblogs.microsoft.com

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Re: How do I inform Windows that I'm writing a binary file?

#5
post #4

The article seems to be taking the position that the C runtime library is not part of "Windows", which feels like a rather odd view to me. What is the stable API that Windows offers to application developers if not that?

The Win32 API. E.g. using WriteFile to write files (https://learn.microsoft.com/en-us/windows/win32/api/fileapi/...)

It wasn't until fairly recently that the C runtime was stably shipped with Windows. Previously you had to install the correct version of the C library alongside your application.

Re: How do I inform Windows that I'm writing a binary file?

#6
post #3

fopen(..., "wb") ?

It's C library taking care of the "b" part for you according to the article.

It's the other way around. It's the C runtime that treats text ("t") mode differently, because the C standard specifies \n as a line delimiter but the Windows convention is \r\n. In text mode C stdio translates between \n and \r\n. In binary mode it does no translation.

Re: How do I inform Windows that I'm writing a binary file?

#7
Going all the way back to the earliest C compilers on DOS. There was a decision made to make “\n” just work on DOS for portability of Unix programs, and to make the examples from the C programming book just work.

But in Unix “\n” is a single byte, and in DOS it is 2. So they introduced text and binary modes for files on DOS. Behind the scenes the library will handle the extra byte. This is not necessary in Unix.

I used to have to be careful about importing files to DOS. Did the file come from Unix?

Re: How do I inform Windows that I'm writing a binary file?

#8
post #4

The article seems to be taking the position that the C runtime library is not part of "Windows", which feels like a rather odd view to me. What is the stable API that Windows offers to application developers if not that?

Indeed, C runtime is not part of windows API, and it's normal to have a program include few different copies of C runtime library due to different modules compiled with different compilers/options.

C runtime library being part of OS is accidental thing in Unix, 16bit and 32bit Windows API even does not use C-compatible ABI (instead, Pascal-compatible one is present)

Re: How do I inform Windows that I'm writing a binary file?

#9
post #5
post #4

The article seems to be taking the position that the C runtime library is not part of "Windows", which feels like a rather odd view to me. What is the stable API that Windows offers to application developers if not that?

The Win32 API. E.g. using WriteFile to write files ( https://learn.microsoft.com/en-us/windows/win32/api/fileapi/... ) It wasn't until fairly recently that the C runtime was stably shipped with Windows. Previously you had to install the correct version of the C library alongside your application.

> The Win32 API. E.g. using WriteFile to write files (https://learn.microsoft.com/en-us/windows/win32/api/fileapi/...)

Which is called from what, if not C? Does windows really offer no API for writing text (rather than bytes) to files? Or does it rely on the application developer to manage line endings in their own code? Neither of those sounds very developer-friendly.

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