Page 49 - Raspberry Pi as a Foundation for Boosting Computer and Technology Literacy

Customizing the system and the shell 3.4
Additionally, a personal recommendation from one of the authors
would be to also add the following aliases for the cp, mv, and rm com-
mands:

alias cp=’cp -v -i’
alias mv=’mv -v -i’
alias rm=’rm -v -i’
These aliases will make these commands more verbose (-v) and in-
teractive (-i), which can help prevent accidental overwrites and dele-
tions by asking for confirmation before executing.

Fetching a random man page
Last, but not least, let us create a bash script, which is essentially a file
that can contain multiple commands along with additional program-
ming syntax, such as variables. This allows a user to create their own
command line tools that can accept flags and arguments. For demon-
stration purposes, we will create a small and simple script for fetching
and displaying random man pages, so the reader can learn more about
various shell commands on their own.
We shall begin by creating an empty file inside the home folder
(name it “randman”, for instance) using the touch command and
then opening it with Nano:

touch randman
nano randman
The first line of any shell script must be a shebang, which informs the
system about which interpreter to use for the script. In our case, we
are using bash, so we must include the following:
#!/bin/bash
Next, let us design a command that will fetch a random man page:

Figure 3.25
The output of the find
command is redirected into awk
and then into sed

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