Readme First

"cat"

This is one of the most flexible Unix commands. We can use to create, view and concatenate files. For our first example we create a three-item English-Spanish dictionary in a file called "dict."
% cat >dict
red rojo
green verde
blue azul

%
stands for "hold the control key down, then tap 'd'". The symbol > tells the computer that what is typed is to be put into the file dict. To view a file we use cat in a different way:
% cat dict
red rojo
green verde
blue azul
%
If we wish to add text to an existing file we do this:
% cat >>dict
white blanco
black negro

%
Now suppose that we have another file tmp that looks like this:
% cat tmp
cat gato
dog perro
%
Then we can join dict and tmp like this:
% cat dict tmp >dict2
We could check the number of lines in the new file like this:
% wc -l dict2
8
The command wc counts things --- the number of characters, words, and line in a file.

No Comment