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What is the use of this switch ?
Find the usage of a switch with out searching through the entire man page. Usage: manswitch [cmd] [switch] Eg: $manswitch grep silent ____________________________ In simple words $man | grep "\-" Eg: $man grep | grep "\-o" This is not a standard method but works.

copy remote ssh session output to local clipboard
ssh from local to remote and pipe output of file to the local clipboard

analyze traffic remotely over ssh w/ wireshark
Please check out my blog article on this for more detail. http://jdubb.net/blog/2009/08/07/monitor-wireshark-capture-real-time-on-remote-host-via-ssh/

Convert ascii string to hex
Here's a version that uses perl. If you'd like a trailing newline: $ perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg; END {print "\n"}'

Start a command on only one CPU core
This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.

Count the number of characters in each line

Sort processes by CPU Usage
Short list about top 10 processes, sorted by CPU usage

Place the argument of the most recent command on the shell
When typing out long arguments, such as: $ cp file.txt /var/www/wp-content/uploads/2009/03/ You can put that argument on your command line by holding down the ALT key and pressing the period '.' or by pressing <ESC> then the period '.'. For example: $ cd 'ALT+.' would put '/var/www/wp-content/uploads/2009/03/ as my argument. Keeping pressing 'ALT+.' to cycle through arguments of your commands starting from most recent to oldest. This can save a ton of typing.

watch iptables counters
This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

Close specify detached screen
-X Send the specified command to a running screen session. -S Option to specify the screen session if you have several screen sessions running. $screen -ls for listing current screens and its sessionname


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