Bash if $？忽略

Question

我正在製作一個postinstall腳本，但由於某種原因，我的菜單不適用於if命令。

它應該回應我選擇的編輯器（呃，現在），但只有回聲emacs。幫幫我？

（下面的代碼）

#!/bin/bash 
if [ $(whoami) != root ] 
then 
    echo "Sorry, this script must be run as root. Try sudo su, and then running it!" 
    exit 1 
fi 

which dialog > /dev/null 

if [ $? = 1 ] 
then 
    echo "Sorry, you need to install dialog first." 
    exit 1 
fi 

choice=$(dialog --no-cancel --backtitle "Jacks Post Install Script" --title "Welcome" --menu "" 20 40 35 1 "Install crap already!" 2 "Enable ssh" 3 "Reboot" 4 "Exit" 3>&1 1>&2 2>&3 3>&-) 

function insstp1 { 
    dialog --cancel-label "No thanks" --extra-button --extra-label "Vim" --ok-label "Emacs" --backtitle "Jacks Post Install Script" --title "Pick an editor!" --yesno "I bet you will pick emacs. Seriusly." 5 40 
    echo $? #emacs 0 vim 3 no 1 
    if [ $? == 0 ] 
    then 
    echo "Emacs" 
    fi 

    if [ $? == 3 ] 
    then 
     echo "Vim" 
    fi 

    if [ $? == 1 ] 
    then 
    echo "nope" 
    fi 
} 

case $choice in 
    1) insstp1 ;; 
    2) enablssh ;; 
    3) reboot ;; 
    4) clear; exit 0 ;; 
esac 

Answer 1

語法錯誤==應-eq當然的避免回波。

dialog --cancel-label "No thanks" --extra-button --extra-label "Vim" --ok-label "Emacs" --backtitle "Jacks Post Install Script" --title "Pick an editor!" --yesno "I bet you will pick emacs. Seriusly." 5 40 
choice2=$? 

if [ $choice2 -eq 0 ]; then 
    echo "Emacs" 
fi 

從docs：

arg1 OP arg2

OP是 '-eq' 中的一個， '-ne'， '-lt'， '-le'， '-gt'或'-ge'。 這些算術二元運算符分別返回true，如果arg1等於，而不是 分別等於，小於，小於或等於，大於或大於 分別等於或等於arg2。 Arg1和arg2可能爲正或負整數。

Answer 2

店面$?和使用案例建設。您正嘗試將第一個對話框的結果存儲在變量選項中，但它將包含stdout。這樣的選擇應該與$?做，以及：

function insstp1 { 
     dialog --cancel-label "No thanks" --extra-button --extra-label "Vim" --ok-label "Emacs" --backtitle "Jacks Post Install Script" --title "Pick an editor!" --yesno "I bet you will pick emacs. Seriusly." 5 40 
     editchoice=$? #emacs 0 vim 3 no 1 
     case ${editchoice} in 
      0) echo "Emacs" ;; 
      3) echo "Vim" ;; 
      1) echo "nope";; 
      *) echo "Let me pick for you ...";; 
     fi 
    } 

dialog --no-cancel --backtitle "Jacks Post Install Script" --title "Welcome" --menu "" 20 40 35 1 "Install crap already!" 2 "Enable ssh" 3 "Reboot" 4 "Exit" 3>&1 1>&2 2>&3 3>&- 
choice=$? 

case ${choice} in 
    1) insstp1 ;; 
    2) enablssh ;; 
    3) reboot ;; 
    4) clear; exit 0 ;; 
esac