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[[!tag open_issue_glibc]]


# IRC, freenode, #hurd, 2012-04-23

    * pinotree spots how our getlogin_r() implementation uses a static
        buffer...
    <braunr> oO
    <pinotree> braunr: yeah, the _r means "reentrantbutnotreally" xD
    <braunr> pinotree: that's amazing ..
    <antrik> pinotree: without having checked the actual implementation, that
      doesn't sound like a problem...
    <antrik> caching doesn't break reentrancy. the problem with the plain
      getlogin() is that a static buffer is *returned to the user*
    <pinotree> antrik: http://paste.debian.net/164727/
    <braunr> ah, caching
    <pinotree> i don't think this is caching at all
    <antrik> pinotree: OK, not actually caching... but same effect as far as I
      can tell
    <antrik> pinotree: or is it the fixed size of the temporary variable you
      are concerned about?
    <pinotree> antrik: my concern was about the "static" of the buffer used for
      the get_login rpc
    <antrik> pinotree: I'm not sure that's a problem. can the login actually
      ever change for a running process?
    <pinotree> dunno
    <pinotree> but if so, it would be pointless to do the rpc every time
      instead of just once
    <antrik> pinotree: true
    * pinotree would just make it non-static and be safe
    <antrik> pinotree: well, one might argue that allocating a KiB of stack
      space is not very friendly, especially in a low-level library...
    <antrik> not sure what the general policy is about such things in libc