我想暂停shell脚本中的输入,并提示用户进行选择。标准的是、否或取消类型问题。如何在典型的bash提示符中完成此操作?


当前回答

您需要:

Bash内置命令(即便携式)检查TTY默认答案超时彩色问题

一小条

do_xxxx=y                      # In batch mode => Default is Yes
[[ -t 0 ]] &&                  # If TTY => Prompt the question
read -n 1 -p $'\e[1;32m
Do xxxx? (Y/n)\e[0m ' do_xxxx  # Store the answer in $do_xxxx
if [[ $do_xxxx =~ ^(y|Y|)$ ]]  # Do if 'y' or 'Y' or empty
then
    xxxx
fi

解释

[[-t 0]]&&read…=>如果TTY,调用命令读取read-n 1=>等待一个字符$'\e[1;32m…\e[0m'=>绿色打印(绿色很好,因为在白色/黑色背景上都可以阅读)[[$do_xxxx=~^(y|y|)$]]=>bash正则表达式

超时=>默认答案为否

do_xxxx=y
[[ -t 0 ]] && {                   # Timeout 5 seconds (read -t 5)
read -t 5 -n 1 -p $'\e[1;32m
Do xxxx? (Y/n)\e[0m ' do_xxxx ||  # read 'fails' on timeout
do_xxxx=n ; }                     # Timeout => answer No
if [[ $do_xxxx =~ ^(y|Y|)$ ]]
then
    xxxx
fi

其他回答

在我的情况下,我需要从下载的脚本中读取。,

curl -Ss https://example.com/installer.sh | sh

在这种情况下,read-ryn</dev/tty行允许它读取输入。

printf "These files will be uploaded. Is this ok? (y/N) "
read -r yn </dev/tty

if [ "$yn" = "y" ]; then
   
   # Yes
else
   
   # No
fi

Bash为此选择了。以下是如何在脚本中使用它:

select result in Yes No Cancel
do
    echo $result
done

这是它使用的样子:

$ bash examplescript.sh
1) Yes
2) No
3) Cancel
#? 1
Yes
#? 2
No
#? 3
Cancel
#?

这是我在脚本/函数中通常需要的:

如果按ENTER键,默认答案为“是”也接受z(如果你在QWERTZ布局上搞混了)接受其他语言(“ja”、“Oui”、…)如果您在函数内部,请处理正确的出口

while true; do
    read -p "Continue [Y/n]? " -n 1 -r -e yn
    case "${yn:-Y}" in
        [YyZzOoJj]* ) echo; break ;;
        [Nn]* ) [[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1 ;; # handle exits from shell or function but don't exit interactive shell
        * ) echo "Please answer yes or no.";;
    esac
done
echo "and off we go!"
read -p "Are you alright? (y/n) " RESP
if [ "$RESP" = "y" ]; then
  echo "Glad to hear it"
else
  echo "You need more bash programming"
fi

更通用的是:

function menu(){
    title="Question time"
    prompt="Select:"
    options=("Yes" "No" "Maybe")
    echo "$title"
    PS3="$prompt"
    select opt in "${options[@]}" "Quit/Cancel"; do
        case "$REPLY" in
            1 ) echo "You picked $opt which is option $REPLY";;
            2 ) echo "You picked $opt which is option $REPLY";;
            3 ) echo "You picked $opt which is option $REPLY";;
            $(( ${#options[@]}+1 )) ) clear; echo "Goodbye!"; exit;;
            *) echo "Invalid option. Try another one.";continue;;
         esac
     done
     return
}