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[[!meta title="getlogin_r"]]
[[!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
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