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

多选版本:

ask () {                        # $1=question $2=options
    # set REPLY
    # options: x=..|y=..
    while $(true); do
        printf '%s [%s] ' "$1" "$2"
        stty cbreak
        REPLY=$(dd if=/dev/tty bs=1 count=1 2> /dev/null)
        stty -cbreak
        test "$REPLY" != "$(printf '\n')" && printf '\n'
        (
            IFS='|'
            for o in $2; do
                if [ "$REPLY" = "${o%%=*}" ]; then
                    printf '\n'
                    break
                fi
            done
        ) | grep ^ > /dev/null && return
    done
}

例子:

$ ask 'continue?' 'y=yes|n=no|m=maybe'
continue? [y=yes|n=no|m=maybe] g
continue? [y=yes|n=no|m=maybe] k
continue? [y=yes|n=no|m=maybe] y
$

它会将REPLY设置为y(在脚本中)。

一种简单的方法是使用xargs-p或gnu-parallel-interactive。

我更喜欢xargs的行为,因为它像其他交互式unix命令一样,在提示符后立即执行每个命令,而不是收集yes以在最后运行。(在完成所需任务后,可以按Ctrl-C键。)

例如。,

echo *.xml | xargs -p -n 1 -J {} mv {} backup/

您可以编写一个函数来测试:

confirm() {
  local ans IFS=;
  while read -rp "$1" -n1 ans;
  do printf '\n';
    case $ans in [Yy]) return 0;;
      [Nn]) return 1;;
    esac;
  done;
}; ## Usage: if confirm "Are you sure? "; then ...

if confirm "Does everything look ok...reboot now? [Y/n]"; then
  echo "rebooting..."
  sleep 5
  reboot
fi

这是我整理的东西:

#!/bin/sh

promptyn () {
    while true; do
        read -p "$1 " yn
        case $yn in
            [Yy]* ) return 0;;
            [Nn]* ) return 1;;
            * ) echo "Please answer yes or no.";;
        esac
    done
}

if promptyn "is the sky blue?"; then
    echo "yes"
else
    echo "no"
fi

我是一个初学者,所以要谨慎对待,但它似乎奏效了。

使用read命令:

echo Would you like to install? "(Y or N)"

read x

# now check if $x is "y"
if [ "$x" = "y" ]; then
    # do something here!
fi

然后你需要的所有其他东西