Tips on changing file permissions in bulk.

First command – changes all files under the current directory to 700 file mode.

find . -type d -exec chmod 0700 {} \;

Second command – changes all directories under the current directory to 600 mode.

find . -type f -exec chmod 0600 {} \;

The ‘history’ commands does not display the exact date and time of the commands executed. It just shows a numeric id followed by  the command executed by the current user. Here is one way of putting a time stamp –

# export HISTTIMEFORMAT=’%F %T >> ‘

To make sure that it works every time you login or restart your machine, put it in $HOME/.bash_profile

Some times you might be able to execute very complex commands and write pages of shell scripts and yet find your-self in a clueless situation, like the seemingly mundane task of setting the data/time in your Linux box from the command line. Here are a couple of ways that might help –

1. Using /etc/localtime and /usr/share/zoneinfo

Create a link to the file in /usr/share/zoneinfo which contains the time zone you want to set your clock to.

#ln -s /usr/share/zoneinfo/America/New_York /etc/localtime

2. Edit /etc/sysconfig/clock

#vi /etc/sysconfig/clock

-set the “ZONE” variable to your region – like “US/Central”

3.  Export command

#Export TZ=America/New_York

4. Simply the date command

format-> #date MMDDhhmmYYYY

#date 070913312010

5. Hardware clock

#hwclock –set –date=”07/09/2010 13:19:55″