Subject: Re: New read & write syscalls
To: None <>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 06/30/1999 15:00:10
> What we want to do (well have done and want to merge into NetBSD) is to:

> 1) Add the idea of "alternate" read semantics.

I'm not sure I like this; the main reason is that two is quite
ridiculous. :)  If you have more than one set of semantics, why not
give it at least an int's worth of possible semantics?  Why just one

On the other hand,

> The call's behavior (read/write, positional/not, alternate/normal
> semantics) is encoded in the flags:

> RDWR_FILEOFFSET		0x01		Use the offset in the file
> 					descriptor, not offset
> RDWR_ALT_SEM		0x02		Use alternate i/o semantics
> RDWR_OTHER_1		0x04		fs-specific flag 1
> RDWR_OTHER_2		0x08		fs-specific flag 2
> RDWR_WRITE		0x10		Do a write

you have, basically, 8 different sets of semantics here.  (I don't see
why you call one of the bits ALT_SEM and the other two OTHER_1 and
OTHER_2; there's really no difference between them.)  I'd rearrange the
bits somewhat, but that's minor.

					der Mouse

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