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Convert a string to "Title Case"
Converts the first letter of each word to upper case

Check if filesystem hangs
When a fs hangs and you've just one console, even # ls could be a dangerous command. Simply put a trailing "&" and play safe

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
remove the host for the .ssh/know_host file

Get a list of ssh servers on the local subnet
--open -sV is not needed if you are only looking for hosts with 22 open

Generate the CPU utilization report
Generated the CPU utilization stats with 5 lines /every 2 seconds. Needs sysstat package to be installed prior to use sar.

Triple monitoring in screen
This command starts screen with 'htop', 'nethogs' and 'iotop' in split-screen. You have to have these three commands (of course) and specify the interface for nethogs - mine is wlan0, I could have acquired the interface from the default route extending the command but this way is simpler. htop is a wonderful top replacement with many interactive commands and configuration options. nethogs is a program which tells which processes are using the most bandwidth. iotop tells which processes are using the most I/O. The command creates a temporary "screenrc" file which it uses for doing the triple-monitoring. You can see several examples of screenrc files here: http://www.softpanorama.org/Utilities/Screen/screenrc_examples.shtml

Sniffing network to generate a pcap file in CLI mode on a remote host and open it via local Wireshark ( GUI ).
Then hit ^C to stop, get the file by scp, and you can now use wireshark like this : $ wireshark /tmp/sniff.pcap If you have tshark on remote host, you could use that : $ wireshark -k -i

List all open ports and their owning executables
Particularly useful on OS X where netstat doesn't have -p option.

Execute MySQL query send results from stdout to CSV
You can, of course, tell MySQL to output results to a file and dictate how to terminate lines, etc. But sometimes you don't have access to the file system MySQL is running on, complicating outputting your results to a CSV, necessitating either annoying hacks or this simple command :D

Undo commit in Mercurial


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