The nl command lists the contents of a file where is each line is prefixed by a line number. For more information about this command, check out its man page. I tested under Mac OS X and Xubuntu 9.04

www.fir3net.com

% cat ph-vmstat.awk

# Return human readable numbers

function hrnum(a) {

b = a ;

if (a > 1000000) { b = sprintf("%2.2fM", a/1000000) ; }

else if (a > 1000) { b = sprintf("%2.2fK", a/1000) ; }

return(b) ;

}

# Return human readable storage

function hrstorage(a) {

b = a ;

if (a > 1024000) { b = sprintf("%2.2fG", a/1024/1024) ; }

else if (a > 1024) { b = sprintf("%2.2fM", a/1024) ; }

return(b) ;

}

OFS=" " ;

$1 !~ /[0-9].*/ {print}

$1 ~ /[0-9].*/ {

$4 = hrstorage($4) ;

$5 = hrstorage($5) ;

$9 = hrnum($9) ;

$10 = hrnum($10) ;

$17 = hrnum($17) ;

$18 = hrnum($18) ;

$19 = hrnum($19) ;

print ;

}

I use terminal with black background on the Mac. Unfortunately, the default ls color for the directory is blue, which is very hard to see. By including the line above in my ~/.bash_profile file, I changed the directory's color to cyan, which is easer to see. For more information on the syntax of the LSCOLORS shell variable:

I tested this command on Mac OS X Leopard

This command asks for the station name and then connects to somafm, Great for those who have linux home entertainment boxes and ssh enabled on them, just for the CLI fiends out there ( I know I'm one of them ;)

Also, don't forget to add this as alias(ie alias somafm="read -p 'Which Station? "; mplayer --reallyquite -vo none -ao sdl

This prints out the first 66 digits of pi.

This takes any number (no more than 66 digits long) from stdin (or on the command line), and tells you how to say it. E.g

outputs "three hundred sixty-five"

Pipe any command through figlet to make the output more awesome. Example:

Useful when you've produced a large file of numbers, and want to quickly see the distribution. The value of y halfway along the x axis is the median. Simple!

Just create the listOfNumbers.txt file with a number on each line to try it out.

G option cause a file to be spacing line by line.

Using mplayer's mencoder, you can merge video files together.

'-oac' specifies the audio encoding (here copy, to just copy and not compress)

'-ovc' specifies the video encoding (same thing).

The symlinks command can show status of all symbolic links, including which links are dangling, which symlinks point to files on other file systems, which symlinks use ../ more than necessary, which symlinks are messy (e.g. having too many slashes or dots), etc. Other useful things it can do include removing all dangling links (-d) and converting absolute links to relative links (-c). The path given must be an absolute path (which is why I used $(pwd) in the example command).

Most of you are probably familiar with the "apropos" command for searching man pages. However, did you know there's a similar command inside of gdb? If, for example, you wanted to know all gdb commands that related to threads, you could type "apropos thread". Type "help some_command" to receive more information about a command. Type "help" by itself to see a list of help topics.

An easy one but nice to keep in mind.

Does life get much easier? Read up about wodim for an understanding of its origins in relation to the older `cdrecord` utility

This command looks for a single file named emails.txt which is located somewhere in my home directory and cd to that directory. This command is especially helpful when the file is burried deep in the directory structure. I tested it against the bash shells in Xubuntu 8.10 and Mac OS X Leopard 10.5.6

Umask is obtained subtracting 7 from each cypher of octal format. I store octal perm format in an array,then for each element of array I subtract 7. The result is the umask.

Clone a partion with tar.

I'm sure almost everybody knows this by now. This command will pull the password for the admin login of any plesk machine.

I use this for connect via sftp to a server listening on a non default ssh port.

The socket.gethostname() call returns the host name of the computer. The socket.gethostbyname_ex() call returns a list of three items: The host name, the list of aliases for this host, and a list of IP addresses. Recall that Python?s array starts with index 0, the socket.gethostbyname_ex(?)[2] expression refers to the list of IP addresses. Finally, the print statement prints out the IP addresses, one per line.

Shred can be used to shred a given partition or an complete disk. This should insure that not data is left on your disk

Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all...

At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p

It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc

So for a specific port, this line returns the calling command line of every thread that handle the associated socket

ifstat, part of ifstat package, is a tool for displaying bandwidth and other statistics. The -n option avoid to display header periodically, the -t option put a timestamp at the beginning of the line.

Works for me on Debian and CentOS