cant delete file as root?

[Mathias Menzel-Nielsen]

Hi

Could someone explain me whats going on here?

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hyperkobold# rm -f /lib/libpthread.so.2
rm: /lib/libpthread.so.2: Operation not permitted

hyperkobold# ls -lah /lib/libpthread.so.2
-r--r--r--  1 root  wheel   159K  1 Mai 23:53 /lib/libpthread.so.2

hyperkobold# chmod u+rw /lib/libpthread.so.2
chmod: /lib/libpthread.so.2: Operation not permitted

hyperkobold# stat /lib/libpthread.so.2
103 1012779 -r--r--r-- 1 root wheel 4050520 162688 "May 18 01:36:33 
2006" "May  1 23:53:56 2006" "May  1 23:53:56 2006" "May  1 23:53:56 
2006" 4096 320 0x20000 /lib/libpthread.so.2
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