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[[!tag open_issue_glibc]]

IRC, unknown channel, unknown date.

    <pinotree> d'oh, broken defines for ioctl()!
    <pinotree> http://paste.debian.net/45021/ ← any idea about this? looks like something fishy with the SIO* defines
    <pinotree> tschwinge: ↑ know anything about this?
    <pinotree> #define _IOT_arpreq       _IOT_SIMPLE (struct arpreq) ← looks like it is missing for bits/ioctls.h
    <pinotree> eglibc patch submitted-ioctl-unsigned-size_t.diff should be pimped a bit

    <pinotree> youpi: while trying to compile ossp-uuid (needed by pgsql 8.4, needed by various other stuff), i found a bug in a hurd libc header
    <youpi> that's possible
    <pinotree> it has a ioctrl() using an id with a value having type 'struct arpreq'
    <youpi> ah, that's not a bug then
    <youpi> see the ioctl section of the porting page of the wiki
    <pinotree> due to the sort of "mangling" done in bits/ioctrls.h, there should be an helper macro for the size of the struct arpreq
    <pinotree> +#define _IOT_arpreq       _IOT_SIMPLE (struct arpreq)  ← adding this before any header was enough
    * pinotree looks
    <youpi> it's not to be done so simply
    <youpi> see the page :)
    <youpi> I'm afraid _IOT_arpreq can't be properly defined
    * pinotree is not finding it...
    <pinotree> the closest i see is http://lists.gnu.org/archive/html/bug-hurd/2006-03/msg00025.html
    <youpi> that's it yes
    <youpi> I mean, that's the kind of thing
    <youpi> but not the wiki page, let me look
    <youpi> http://www.gnu.org/software/hurd/hurd/porting/guidelines.html
    <pinotree> i also saw a glib patch adding few types like that (char, short, int)
    <youpi> yes that's the same kind of thing
    <pinotree> i see
    <youpi> setting it to _IOT_SIMPLE(struct arpreq) would probably work with 32bit gnumach and 32bit userland, but may not with e.g. 64bit gnumach and 32bit userland and such
    <pinotree> hmmm, sockaddr,sockaddr,int,sockaddr,char[16]
    <pinotree> so basically it would support at most 3 elements in a passed struct?
    <pinotree> s/elements/fields/
    <youpi> 3 kinds of fields
    <youpi> as you provide a count
    <pinotree> youpi: so basically: #define _IOT_arpreq _IOT (_IOTS (struct sockaddr), 3, _IOTS (int), 1, _IOTS (char), 16) ?
    <pinotree> ie the order of the fields in the struct does not matter, it seems?
    <youpi> the order of the fields does matter
    <youpi> as this encodes how mig will read the struct to send them
    <pinotree> uhm
    <youpi> also, _IOTS(struct sockaddr) won't work
    <pinotree> yeah i should define it too
    <youpi> no, it even needs to be replaced by its content
    <pinotree> ah
    <pinotree> it is possible to compose the _IOTS()?
    <pinotree> (to build structs with more than 3 kind of fields)
    <youpi> no
    <pinotree> d'oh
    <youpi> that's a hard shortcoming of the whole ioctl encoding
    * pinotree scratches his head
    <youpi> there's no way but redefining ioctl(), really
    <youpi> it was a funny trick to encode it this way, but unrealistic
    <pinotree> i see, yes
    <youpi> not to mention ioctls which contain pointers, which just can not be passed to mig
    <pinotree> indeed
    <youpi> actually it's not mach's ioctl issue
    <youpi> as mach doesn't know ioctl
    <youpi> but the hurd ioctl interface
    <pinotree> right
    <youpi> which might end up in mach, other processes, other machines, etc.
    * pinotree s/Mach/Hurd/ :)