Observe the output of ‘ls – l’ command, the last 3 bits of the first column represents
A. file type
B. permissions for the file owner
C. permissions for the the group
D. permissions for other users
查看答案
If chmod 444 fido is executed successfully, then permission of fido is
A. -rwxr-xr-x
B. -rwxr--r--
C. -r--r--r--
D. -r-xr-x—x
The most convenient command or operation to terminate a foreground process (without signal masking) is
A. kill
B. Ctrl+c
C. halt
D. shutdown
About command ‘# mv abc xyz’, which statement is wrong:
A. If abc is a normal file and xyz doesn't exist before, then this command will change the file name abc to xyz.
B. If abc is a normal file and xyz is a directory, this command will move file abc into directory xyz.
C. If abc is a directory and xyz is also a directory, this command will make abc to be the subdirectory of xyz.
D. If abc is a directory and xyz is a normal file, this command will overwrite xyz, i.e. xyz will lost.
File wang.tar.gz in the current directory. The correct tar command to extract this file is:
A. tar zcvf wang.tar.gz
B. tar zxvf wang.tar.gz
C. tar jcvf wang.tar.gz
D. tar jxvf wang.tar.gz
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