after class fixes

modules/resources/solution_raspberrypi.md

@@ -69,6 +69,14 @@ Now we have all the usernames we need and we can save this to a file by redirect
 cat accounts.csv | cut -d "," -f 4 | tail -n +2 | cut -d ":" -f 1 | cut -d "@" -f 2 > usernames.list
 ```
 
+Vladimir pointed out a handy way to replace the `tail` command with a `grep`.
+It's less cryptic and would go as follows.
+The result is the same but the way we get there is slightly different.
+
+```bash
+cat accounts.csv | grep "@" | cut -d "," -f 4 | cut -d ":" -f 1 | cut -d "@" -f 2
+```
+
 ### The $PASSWORD
 
 To extract the password we need to combine two field from the CSV file.
@@ -80,6 +88,14 @@ Don't forget the man pages!
 cat accounts.csv | awk -F "," '{print $2 $3}' | tail -n +2
 ```
 
+Sarah found an interesting feature to `cut` where you can show multiple fields at the same time.
+The syntax is quite easy but it introduces a `,` we'll have to get rid of afterwards.
+Combined with Vladimir's approach this gives a more comprehensible command.
+
+```bash
+cat accounts.csv | grep "@" | cut -d "," -f 3,2 | tr -d ","
+```
+
 If you feel like making the password complexer, you can try to add in extra data into the `awk` command, or even append random numbers to the end.
 How would you do this?
 
@@ -109,8 +125,6 @@ Last but not least, don't forget to add execution permissions to this script wit
 ```bash
 #!/bin/bash
 
-LINE=$1
-
 head -$1 usernames.list | tail -1
 head -$1 passwords.list | tail -1
 head -$1 groups.list | tail -1
@@ -144,8 +158,6 @@ At the last line we *use* the variables to create a message we display on our ST
 ```bash
 #!/bin/bash
 
-LINE=$1
-
 USERNAME=$(head -$1 usernames.list | tail -1)
 PASSWORD=$(head -$1 passwords.list | tail -1)
 GROUP=$(head -$1 groups.list | tail -1)
@@ -164,8 +176,6 @@ This gives us the following script.
 ```bash
 #!/bin/bash
 
-LINE=$1
-
 USERNAME=$(head -$1 usernames.list | tail -1)
 PASSWORD=$(head -$1 passwords.list | tail -1)
 GROUP=$(head -$1 groups.list | tail -1)
@@ -186,8 +196,6 @@ Nice!
 ```bash 
 #!/bin/bash
 
-LINE=$1
-
 USERNAME=$(head -$1 usernames.list | tail -1)
 PASSWORD=$(head -$1 passwords.list | tail -1)
 GROUP=$(head -$1 groups.list | tail -1)
@@ -210,8 +218,6 @@ We probably want to use `/bin/bash` for this option!
 ```bash 
 #!/bin/bash
 
-LINE=$1
-
 USERNAME=$(head -$1 usernames.list | tail -1)
 PASSWORD=$(head -$1 passwords.list | tail -1)
 GROUP=$(head -$1 groups.list | tail -1)
@@ -224,8 +230,6 @@ useradd $USERNAME -m -G $GROUP -s "/bin/bash"
 
 echo "setting password: $PASSWORD for $USERNAME"
 echo $USERNAME:$PASSWORD | chpasswd
-
-echo "adding $USERNAME to $GROUP"
 ```
 
 This is getting pretty close to perfect!
@@ -249,7 +253,6 @@ Don't worry if this looks to complicated at the moment, we'll do this exercise a
 ```bash
 #!/bin/bash
 
-FILE=$1
 LINES=$(cat $1)
 
 for LINE in $LINES;