Keeping up tradition

What better subject for the first post on a new personal tech blog than a good old ‘Hello World!’.

It also gives me the opportunity to check that codeblocks in this theme are working correctly.

Simple echo command in Bash

Typing echo followed by ‘Hello World!’ would result in the below (the $ sign shows the terminal is waiting for input):

$ echo 'Hello World!'
Hello World!
$

Another way to use echo in Bash

As well as writing text into the terminal, the echo command when combined with the file redirection operator ‘>’ can also write text to a file. This command will overwrite all contents of the file, so please use it carefully.

A simple example of using this to write ‘Hello World!’ to a file named ‘hello.txt’ would look like:

$ echo 'Hello World!' > hello.txt
$

Please note that there should be no output in the terminal. However, you can check that it worked by using the ‘cat’ command to print the contents of the file:

$ cat hello.txt
Hello World!
$

As mentioned above, the redirection operator will overwrite the file entirely, but if you want to append text to a file, you can use ‘»’. An example of using this command would be:

$ echo 'Hello World!' > newfile.txt
$ cat newfile.txt
Hello World!
$ echo 'this is now the first line' > newfile.txt
$ cat newfile.txt
this is now the first line
$ echo 'and this is the second line' >> newfile.txt
$ cat newfile.txt
this is now the first line
and this is the second line
$