libc problem after yum upgrade

[Stefan Thierl]

i ran yum upgrade on a fedora-devel box last week, after which 90% of my
system binaries refused to run, with messages similar, but not identical
to the following:

ImportError: /lib/librt.so.1: symbol __librt_disable_asynccancel,
version GLIBC_PRIVATE not defined in file libc.so.6 with link time
reference

the extent of this breakage was that my machine was rendered unusable,
with things like networking failing completely, and even simple console
tools such as ls refusing to run. i fixed almost everything by obtaining
a replacement librt.so from a friend who was also running fedora-devel,
and since then everything has worked fine except yum, which fails like
so:

[root at oiktest root]# yum
Traceback (most recent call last):
  File "/usr/bin/yum", line 22, in ?
    import yummain
  File "/usr/share/yum/yummain.py", line 22, in ?
    import clientStuff
  File "/usr/share/yum/clientStuff.py", line 18, in ?
    import rpm
ImportError: /lib/librt.so.1: symbol __librt_disable_asynccancel,
version GLIBC_PRIVATE not defined in file libc.so.6 with link time
reference

i've also obtained replacement libc.so files from another friend running
devel, but that hasn't made any difference. i yum upgraded two other
similar machines on the same day with no problems. has anybody got any
idea how i could fix this and get back up to date? i don't fancy doing
another clean install right now :)


-- 
Stefan Thierl
Systems Administrator
Hoxton Bibliotech
239 Old Street
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