[ECOS] Re: open, close, read, write ????

[Bart Veer <bartv@cygnus.co.uk>]

>>>>> "Stuart" == Stuart Adams <sja@brightstareng.com> writes:

    Stuart> Any plans to add the open(), close(), read(), write()
    Stuart> calls to eCos ??? I have alot of existing code the assumes
    Stuart> they exist. (I guess I could create stubs routines for
    Stuart> open() et al. that call fopen(), fclose() ... but this
    Stuart> seems a little backwards.)

The question here is "What exactly can you open()?". Right now there
are no file systems available for eCos. There is some primitive
support in the C library which allows you to fopen() the various
device drivers amenable to this, but that may not be what you are
after. 

There is a basic issue here of how to manage the I/O namespace. Some
embedded systems will have only a single block device on which I/O is
possible, for example a ROM disk. Other embedded systems may support
dynamic various different block devices, for example both a network
file system and flash disk support. In a general solution all device
drivers would be accessible via /dev/whatever (as well as providing
their own lower-level interfaces for people who want more control
over what the devices are doing). The challenge is to satisfy all the
different requirements in a way that does not impose unnecessary
overheads on smaller systems.

Work is certainly planned in this area, but there are a few other
things that have higher priority right now and work may not start for
a couple more months. Once work begins the first step will be to
generate a public discussion document and invite comments from the
development community.

Bart Veer // eCos net maintainer