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File mode: char/block special files and permission bits Göran Weinholt (31 Jul 2019 14:25 UTC)
Re: File mode: char/block special files and permission bits Lassi Kortela (31 Jul 2019 15:32 UTC)

Re: File mode: char/block special files and permission bits Lassi Kortela 31 Jul 2019 15:32 UTC

> That turns out to be a problem in the description, where I say
> "Returns ... mode (permission bits).... " I should either add
> something before the close paren, or drop the parenthetical comment.
>
> Except for that error, the SRFI, and the Chibi Scheme implementation
> of it return all the bits, which are necessary for the following
> file-info-directory?, file-info-fifo? etc. predicates, no masking is
> intended to be specified in the SRFI.

Speaking from experience: the fact that the mode bits contain both
permissions and file type is a perennial source of confusion in the OS
APIs of many languages. It's a historical accident that's only intuitive
to Unix diehards.

I would suggest giving access to the full mode bits as Göran suggests,
but name them something stupidly obvious like

- file-info:full-unix-mode-bits

There could additionally be separate procedures:

- file-info:unix-permission-bits
- file-info:unix-file-type-bits