I have a constantly running script that I output to a log file:
script.sh >> /var/log/logfile
I'd like to add a timestamp before each line that is appended to the log. Like:
Sat Sep 10 21:33:06 UTC 2011 The server has booted up. Hmmph.
Is there any jujitsu I can use?
Try executing the following under a bash shell echo "Reboot your instance!"
On my installation:
root@domU-12-31-39-04-11-83:/usr/local/bin# bash --version
GNU bash, version 4.1.5(1)-release (i686-pc-linux-gnu)
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
root@domU-12-31-39-04-11-83:/usr/local/bin# uname -a
Linux domU-12-31-39-04-11-83 2.6.35-22-virtual #35-Ubuntu SMP Sat Oct 16 23:57:40 UTC 2010 i686 GNU/Linux
root@domU-12-31-39-04-11-83:/usr/local/bin# echo "Reboot your instance!"
-bash: !": event not found
Can anyone please explain what is "bash events?" I've never heard this concept before. Also, how should I output "!" at the end of the sentence?
I just wondered what exactly the difference between
[[ $STRING != foo ]]
and
[ $STRING != foo ]
is, apart from that the latter is POSIX-compliant, found in sh and the former is an extension found in bash.
When I have dircolors defined life is full of... color.
When I pipe ls through less to scroll around I lose the colors.
Any suggestions?
I know there was a command on Unix that I could use to monitor a file and see changes that are getting written to it. This was quite useful especially for checking log files.
Do you know what it is called?