How to decompress multiple files on Linux

To unzip multiple zipped .zip files:

for file in *.zip; do unzip "${file}"; done

To unzip multiple zipped .gz files;

gunzip *.gz

To unzip multiple zipped .bz2 files;

bunzip2 *.bz2

To extract multiple .tar.gz files;

for file in *.tar.gz; do tar zxf "${file}"; done

To extract multiple .tar.bz2 files;

for file in *.tar.bz2; do tar jxf "${file}"; done

Generate ssh key on Mac OS

Open a terminal and enter the following commands,

$ cd ~/

$ ssh-keygen -t rsa

It will ask you to specify the location, so just use the default one (~/.ssh/id_rsa.pub) by pressing return. If you do not need passphrase, just press return. After that, you may get something like this,

Your identification has been saved in /Users/username/.ssh/id_rsa.

Your public key has been saved in /Users/username/.ssh/id_rsa.pub.

The key fingerprint is:

45:a0:5b:34:23:73:8c:43:03:27:b5:92:9d:80:b1:7d

yourusername@XXXmac

The key's randomart image is:


+--[ RSA 2048]----+
|     ...  o*+=*o.|
|      ... = -+++ |
|        .. + ..+.|
|         ..     .|
|        P  .     |
|         .. Y    |
|           x     |
|          .      |
|                 |
+-----------------+

Then you can find your public key in the "file ~/.ssh/id_rsa.pub".

How to format a hard drive for Mac OS

Video tutorial links:

http://www.youtube.com/watch?v=8te1bg07MsQ

http://www.youtube.com/watch?v=WzQF0Qo5Kv0

Command line to check the version

We can use this command to check whether the linux is 32 bits or 64 bits:

uname -m

if the output is i686, then it is 32 bits;

if the output is x86_64, then it is 64 bits.

How to change the icon of an application

First of all, copy the new icon into clipboard;

Then, open the Info window for the application (File » Get Info, or Command-I), click the icon in that window (a blue border will appear), and paste in a new icon.