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[[!meta copyright="Copyright © 2012 Free Software Foundation, Inc."]]

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[[!meta title="libnetfs: io_map"]]

[[!tag open_issue_hurd]]

This hampers [[hurd/translator/nfs]] usability, for example:

    $ fsysopts ./
    /hurd/nfs [...]
    $ cp -a /bin/true ./
    cp: failed to preserve authorship for `./true': Operation not supported
    $ ./true
    $ /lib/ld.so /bin/true
    $ /lib/ld.so $PWD/true
    [...]/true: error while loading shared libraries: [...]/true: failed to map segment from shared object: Error 1073741869

IRC, freenode, #hurd, 2012-03-14:

    <civodul> i just realized that ld.so uses mmap unconditionally
    <civodul> so executables or shared libs can't be used off a netfs-based
      file system
    <civodul> that's annoying
    <tschwinge> civodul: Do you know what it takes to fix libnetfs?  I have no
      idea.
    <tschwinge> Never looked at it.
    <civodul> tschwinge: implementing io_map
    <civodul> but i think the idea is that io_map typically isn't convenient
      for network file systems
    <civodul> which is why it doesn't have it
    <civodul> the GCS says "thou shall not require mmap" ;-)

<http://lists.gnu.org/archive/html/bug-hurd/2001-10/msg00306.html>.  Analysis
to be found on [[glibc/mmap]] page.