LinuxQuestions.org - Interesting linux commands

I m writing an article over interesting linux commands .
I would be glad if someone adds to the list.

1)Command to find the Installation date of O.S.
2)How to find Most Used Linux commands of your machine?

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1)Command to find the Installation date of O.S.

Still dont remember last time you have installed an OS.
Dont worry Following command can help you get the exact date.

Method 1:

Code:

# tune2fs -l /dev/root | grep created

Filesystem created: Wed Oct 13 19:08:13 2010

Method 2:
First find the location of install.log in your machine.

Code:

# find / -name install.log

/root/install.log

then you can check the detail using ls -ltr /root/install.log.

Code:

# ls -ltr /root/install.log

-rw-r--r-- 1 root root 14038 Oct 13 13:40 /root/install.log

in above example install.log is created on Oct 13 So the OS is installed on 13th Oct.
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2)How to find Most Used Linux commands of your machine?

I know the question is quite simple but yet interesting.You can use following command to find out which is the most used command of your Linux Machine .

Code:

# cut -f1 -d" " .bash_history | sort | uniq -c | sort -nr | head -n 10

113 cd

98 ls

83 xm

64 cat

59 dir

59 df

55 find

48 sysctl

42 vi

36 mount

other way of doing the same thing.

Code:

# history | awk '{print $2}' | awk 'BEGIN {FS="|"}{print $1}' | sort | uniq -c | sort -n | tail | sort -nr

113 cd

98 ls

80 xm

64 cat

59 dir

59 df

55 find

48 sysctl

42 vi

36 mount

from above output its very clear that "cd" is the most used command in my distribution.
I know there are no practical usage of this command but sometime its good to know which command stress your fingers :)

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