ones and zeros
Recently I have been introduced to the top command line tool. This tool is very useful in viewing the top processes running on a machine and their CPU and Memory usage. I have included a screen shot of the top command’s output.
Some useful options are the i option which allows you to toggle back and forth between viewing and not viewing idle processes.
And the M option which allows you to sort the processes by memory usage.
In order to save myself from painstakingly typing the same commands over and over again I invested a little time in learning about the Unix history command. One workflow that I have found very useful is the following:
!vi – repeats the last vi command that I typed (apply this to any command)
!! – repeats the last command that I typed
history – prints out the entire history with the associated number for each command
example:
100 – vi info.txt
101 – mv info.txt noinfo.txt
history > myhistory.txt – this will store the contents of my history in a file for later reference
Using the information derived from history I can then do the following:
!100 – this will perform the command vi info.txt
more !:$ – this will take the first argument of the last command and perform a new command on it. So in this instance I will essentially have more info.txt.
Amazing stuff, hunh!
There is no Print Screen button on the Mac, so you must type the following to print the screen.
Shift + Command + 3 – This will send a png file to your desktop of entire page
Shift + Command + 4 – This will allow you to select what portion of the screen to capture
Here are some more vi Commands that I have learned recently:
j – move down one line
k – move up one line
ndd – delete n number of characters
And apparently there are many, many more. To be continued…