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Why can't root execute when executable bits are not set?

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http://unix.stackexchange.com – root user can write to a file even if its write permissions are not set. root user can read a file even if its read permissions are not set. root user cannot execute a file when its execute permissions are not set. Why? user$ echo '#!'$(which bash) > file user$ chmod 000 file user$ ls -l file ---------- 1 user user 12 Jul 17 11:11 file user$ cat file # Normal user cannot read cat: file: Permission denied user$ su root$ echo 'echo hello' >> file # root can write root$ cat file # root can read #!/bin/bash echo hello root$ ./file (HowTos)

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Submitted by Danial on 07/17/2012 – Made popular on 07/17/2012

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