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after class fixes

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waldek 2021-04-21 15:40:18 +02:00
parent c35934b33b
commit f7e19ebc11
1 changed files with 16 additions and 13 deletions
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modules/resources/solution_raspberrypi.md
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@ -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 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 ### The $PASSWORD
To extract the password we need to combine two field from the CSV file. 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 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. 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? 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 ```bash
#!/bin/bash #!/bin/bash
LINE=$1
head -$1 usernames.list | tail -1 head -$1 usernames.list | tail -1
head -$1 passwords.list | tail -1 head -$1 passwords.list | tail -1
head -$1 groups.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 ```bash
#!/bin/bash #!/bin/bash
LINE=$1
USERNAME=$(head -$1 usernames.list | tail -1) USERNAME=$(head -$1 usernames.list | tail -1)
PASSWORD=$(head -$1 passwords.list | tail -1) PASSWORD=$(head -$1 passwords.list | tail -1)
GROUP=$(head -$1 groups.list | tail -1) GROUP=$(head -$1 groups.list | tail -1)
@ -164,8 +176,6 @@ This gives us the following script.
```bash ```bash
#!/bin/bash #!/bin/bash
LINE=$1
USERNAME=$(head -$1 usernames.list | tail -1) USERNAME=$(head -$1 usernames.list | tail -1)
PASSWORD=$(head -$1 passwords.list | tail -1) PASSWORD=$(head -$1 passwords.list | tail -1)
GROUP=$(head -$1 groups.list | tail -1) GROUP=$(head -$1 groups.list | tail -1)
@ -186,8 +196,6 @@ Nice!
```bash ```bash
#!/bin/bash #!/bin/bash
LINE=$1
USERNAME=$(head -$1 usernames.list | tail -1) USERNAME=$(head -$1 usernames.list | tail -1)
PASSWORD=$(head -$1 passwords.list | tail -1) PASSWORD=$(head -$1 passwords.list | tail -1)
GROUP=$(head -$1 groups.list | tail -1) GROUP=$(head -$1 groups.list | tail -1)
@ -210,8 +218,6 @@ We probably want to use `/bin/bash` for this option!
```bash ```bash
#!/bin/bash #!/bin/bash
LINE=$1
USERNAME=$(head -$1 usernames.list | tail -1) USERNAME=$(head -$1 usernames.list | tail -1)
PASSWORD=$(head -$1 passwords.list | tail -1) PASSWORD=$(head -$1 passwords.list | tail -1)
GROUP=$(head -$1 groups.list | tail -1) GROUP=$(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 "setting password: $PASSWORD for $USERNAME"
echo $USERNAME:$PASSWORD | chpasswd echo $USERNAME:$PASSWORD | chpasswd
echo "adding $USERNAME to $GROUP"
``` ```
This is getting pretty close to perfect! 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 ```bash
#!/bin/bash #!/bin/bash
FILE=$1
LINES=$(cat $1) LINES=$(cat $1)
for LINE in $LINES; for LINE in $LINES;