# rm /etc/ld.so.cache
# ldconfig -v
...
libcidn-2.19b.0.so -> libcidn-2.19b.0.so
...
# rm /lib/libcidn-2.19b.0.so
rm: cannot remove '/lib/libcidn-2.19b.0.so': No such file or directory
# ln -s /lib/x86_64-linux-gnu/libcidn-2.19.so /lib/libcidn-2.19b.0.so
ln: failed to create symbolic link '/lib/libcidn-2.19b.0.so': File exists
# ldconfig -p | grep libcidn
libcidn.so.1 (libc6,x86-64, OS ABI: Linux 2.6.24) => /lib/x86_64-linux-gnu/libcidn.so.1
libcidn.so.1 (libc6, OS ABI: Linux 2.6.24) => /lib/i386-linux-gnu/libcidn.so.1
libcidn.so.1 (libc6, OS ABI: Linux 2.6.24) => /lib32/libcidn.so.1
libcidn.so (libc6,x86-64, OS ABI: Linux 2.6.24) => /usr/lib/x86_64-linux-gnu/libcidn.so
libcidn-2.19b.0.so (libc6,x86-64) => /lib/libcidn-2.19b.0.so
# ls -al /lib
total 312
drwxr-xr-x 23 root root 4096 Jan 7 00:27 .
drwxr-xr-x 23 root root 4096 Jan 6 23:42 ..
drwxr-xr-x 2 root root 4096 Sep 7 21:32 apparmor
lrwxrwxrwx 1 root root 21 Jun 4 2014 cpp -> /etc/alternatives/cpp
drwxr-xr-x 3 root root 4096 Jun 4 2014 crda
drwxr-xr-x 2 root root 4096 Jun 4 2014 discover
drwxr-xr-x 63 root root 24576 Jan 6 23:30 firmware
drwxr-xr-x 2 root root 4096 Jun 4 2014 hdparm
drwxr-xr-x 2 root root 4096 Jan 6 22:10 i386-linux-gnu
drwxr-xr-x 2 root root 4096 Jun 4 2014 ifupdown
drwxr-xr-x 2 root root 4096 Jun 29 2015 init
-rwxr-xr-x 1 root root 71512 Dec 23 2013 klibc-P2s_k-gf23VtrGgO2_4pGkQgwMY.so
lrwxrwxrwx 1 root root 25 Feb 25 2015 ld-linux.so.2 -> i386-linux-gnu/ld-2.19.so
lrwxrwxrwx 1 root root 17 Jan 8 2014 libip4tc.so.0 -> libip4tc.so.0.1.0
-rw-r--r-- 1 root root 27392 Jan 8 2014 libip4tc.so.0.1.0
lrwxrwxrwx 1 root root 17 Jan 8 2014 libip6tc.so.0 -> libip6tc.so.0.1.0
-rw-r--r-- 1 root root 31520 Jan 8 2014 libip6tc.so.0.1.0
lrwxrwxrwx 1 root root 16 Jan 8 2014 libiptc.so.0 -> libiptc.so.0.0.0
-rw-r--r-- 1 root root 5816 Jan 8 2014 libiptc.so.0.0.0
lrwxrwxrwx 1 root root 20 Jan 8 2014 libxtables.so.10 -> libxtables.so.10.0.0
-rw-r--r-- 1 root root 47712 Jan 8 2014 libxtables.so.10.0.0
drwxr-xr-x 3 root root 4096 Jun 4 2014 lsb
drwxr-xr-x 2 root root 4096 Jan 6 23:30 modprobe.d
drwxr-xr-x 5 root root 4096 Jan 6 22:46 modules
drwxr-xr-x 2 root root 4096 Jun 29 2015 modules-load.d
drwxr-xr-x 3 root root 4096 Dec 18 2014 plymouth
drwxr-xr-x 3 root root 4096 Jun 4 2014 recovery-mode
drwxr-xr-x 2 root root 4096 Jul 15 2014 resolvconf
drwxr-xr-x 3 root root 4096 Jan 6 11:20 systemd
drwxr-xr-x 15 root root 4096 Jun 4 2014 terminfo
drwxr-xr-x 4 root root 4096 Jan 6 11:23 udev
drwxr-xr-x 2 root root 4096 Jun 4 2014 ufw
drwxr-xr-x 4 root root 12288 Jan 7 11:08 x86_64-linux-gnu
drwxr-xr-x 2 root root 4096 Jun 4 2014 xtables