試著讓 printf 語句在 bash for 迴圈中執行一次

Question

我想知道我將如何做

printf "Credentials found!"

當找到多個憑證時僅一次。

Attempting Dictionary Attack on 192.168.91.130

Credentials Found!

Log into the telnet server by running telnet -l admin 192.168.91.130

When prompted enter the password found 'admin'

Credentials Found!

Log into the telnet server by running telnet -l sfx 192.168.91.130

When prompted enter the password found 'toor'

循環bash：

for i in "${!user[@]}"; do
    printf "The Username & Password is %s : %s\n\n" "${user[i]}" "${pass[i]}" >> SSH-Credentials.txt

    printf "${NCB}Credentials Found!${NC}\n\n"

    printf "Log into the SSH server by running ${YELLOW}ssh ${user[i]}@$ip${NC}\n\nWhen prompted enter the password found ${YELLOW}'${pass[i]}'\n"
    printf "${NC}\n"
done

Answer 1

$i您可以進行以下測試：

    [[ "$i" -lt 1 ]] && printf "I am only printed once\n"

    # OR
    (( i < 1 )) && printf "I am only printed once\n"

    # OR
    ! (( i )) && printf "I am only printed once\n"

    # OR
    [ "$i" -lt 1 ] && printf "I am only printed once\n"

    # OR
    if [[ "$i" -lt 1 ]]; then
        printf "I am only printed once\n"
    fi

假設你不使用關聯 bash 數組。

簡而言之：如果索引小於 1，則列印。

---

為了方便閱讀，我也會分解這些行。路寬。請注意，您也可以說：

printf '%s %s some long text' \
"$var1" "$var2"

使用大寫字母表示變數也是一個壞習慣。

資訊通常也應列印在stderr， 所以>&2。

還會使用：

prinf '%s@%s' "${user[i]}" "$ip" >&2

代替：

prinf "${user[i]}@$ip" >&2

Answer 2

user如果數組中有元素，則輸出標頭。

if [[ ${#user[@]} -gt 0 ]]; then
    printf '%sCredentials Found!%s\n\n' "$NCB" "$NC"
fi

然後做你的循環。

for i in "${!user[@]}"; do
    printf 'The Username & Password is %s : %s\n\n' "${user[i]}" "${pass[i]}" >> SSH-Credentials.txt

    cat <<END_MESSAGE
Log into the SSH server using ${YELLOW}ssh ${user[i]}@$ip$NC
When prompted, enter the password found: ${YELLOW}${pass[i]}$NC

END_MESSAGE
done