As the second week rolled in,We had to present a certain topic, and My topic was the UNIX command join.

join by definition is a Unix command which joins lines of two files on a common field. It can be used to join two files by selecting fields within the line and  joining the files on them. The result is written to standard output. P.S join expects that files will be sorted before joining.

To join two files using the join command files must have  identical join fields. The default join field is the first field  delimited by blanks. For the following example there are two files food.txt and food2.txt

These files share a common field as the first field and can be joined.
Thus these files are joined on the common fields.

To join files using different fields the -1 and -2 options can be passed to join. Consider This example of food.txt and food2.txt

Here the common field for food is the 3rd field, and for food2 is the 1st field

These files can be joined by specifying the fields that should be used  to join the files. Common to both files is the numbering. In food.txt this is the third field. In food2.txt this is the first field. The files can be joined using -1 and -2 by specifying these fields.

We were introduced to an editor know as Emacs.

Emacs is a text editor mainly used by Programmers, Engineers, System admins etc. Mainly because it  provides typed commands and special key combinations that lets you add, delete,and manipulate words, letters, lines, and other units of text.

In Emacs, we use keystrokes and shortcuts to navigate and edit in Emacs which gives us more agility and efficiency (which is something i need the most since i am one-handed). The commands generally involve the Ctrl key (abbreviated as C)  or the Alt key, known as Meta key (abbreviated as M).

Listed below are some commands used in Emacs :

C-f Move forward a character
C-b Move backward a character
M-f Move forward a word
M-b Move backward a word
C-n Move to next line
C-p Move to previous line
C-a Move to beginning of line
C-e Move to end of line
M-a Move back to beginning of sentence
M-e Move forward to end of sentence
C-x C-s Save file

We were also asked to learn about Emacs and to get familiar with the editor. We were also referred to a video-series by Noufal Ibrahim known as Emacs Movies, which covered the basics of Emacs.

As we approached the end of the week, we were given bare minimum introduction to Git, and was also referred to " Pro Git ", written by Scott Chacon and Ben Straub.

Stay tuned for next week, we would be discussing about Git and how it is  effectively used in version control.