CODEWITHSUNDEEP
shell
Jazuly
Jazuly

Reputation: 1424

How to use case statement on shell script linux

im trying to create a script that check if user already registered before than add number after username for example username1 and will keep looping after i got unique username.

here what i try

username="tes2"
password="tes2"
exists=$(grep -c "^$username:" /etc/passwd)
case=$exists
i=1

while true
do
    case "$case" in
        *)
            echo 'generate new user'
            i=$(( $i + 1 ))
            username="$username""$i"
            exists=$(grep -c "^$username:" /etc/passwd)
            case=$exists;;
        0) 
            pass=$(perl -e 'print crypt($ARGV[0], "password")' $password)
            useradd -m -p "$pass" "$username"
            echo 'success add $username' 
            break;;
    esac
done

echo "Quit"

when i run this script, it keep generate new user.

Upvotes: 0

Views: 208

Answers (2)

Steve Col
Steve Col

Reputation: 1

#!/bin/bash


check_passwd() {
    if [ ! -f ./passwd_copy.txt ]; then
    echo "brak pliku passwd_copy.txt, aby utworzyc uruchom skrypt z poleceniem -INIT";
    exit 1
    fi
}

case $1 in
    "-AUTHOR")
        echo "Autor skryptu: $autor";
        echo "Grupa szkoleniowa $grupa";
        echo "Nazwa skryptu: $0";
    ;;
    "-INIT")
        if [ $(cp /etc/passwd ./passwd_copy.txt) ] ; then
        echo "kopia nie ok";
        else
        echo "kopia ok";
        fi
    ;;
    "-FIND")
        check_passwd
        if [ -z "$2" ]; then
        echo "brak ciagu do wyszukania"
        exit 1
        fi
        grep "$2" passwd_copy.txt > wynik_$(date +%d-%m-%Y).txt 
    ;;
    "-COLUMNS")
        check_passwd
        if [ -z "$2" ]; then
        echo "Brak numeru kolumny"
        exit 1
        fi
        awk -v col="$2" -F: '{print $col}' passwd_copy.txt 1>$2
    ;;
    "-RIGHTS")
        check_passwd
        if [ -z "$2" ] || [ -z "$3" ]; then
        echo "brak katalogu lub praw"
        exit 1
        fi
        for file in "$2"/*; do
        if [ -f "$file" ]; then
        chmod "$3" "$file"
        echo "zmieniono prawa dla pliku $file"
        fi
        done
    ;;
    *)
        echo "Możliwe do wpisania parametry to -AUTHOR -INIT -FIND -COLUMNS -RIGHTS";
    esac

Upvotes: 0

Nate Eldredge
Nate Eldredge

Reputation: 57997

https://tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_03.html

The commands in the COMMAND-LIST for the first match are executed.

https://www.gnu.org/software/bash/manual/bash.html#Conditional-Constructs

case will selectively execute the command-list corresponding to the first pattern that matches word.

* always matches so it's always executed. If you want the 0 case to execute when it matches, put it before the * case.

Upvotes: 5

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