如何創建 bash 腳本，替代“goto”和“labels”

批量：

@echo off
:step1
if exist "file1.txt" (GOTO step2) ELSE (GOTO X)
:step2
if exist "file2.txt" (GOTO Z) ELSE (GOTO Y)

:X
run the script from the beginning and file1.txt and file2.txt are created and the rest of the script is executed
:Y
run the commands to file1.txt and run the rest of the script
:Z
run the commands to file2.txt and run the rest of the script

我知道 bash 中不存在“goto”和“labels”，但是在 bash 中做類似於上述操作的替代方法是什麼？

試圖：

#!/bin/bash
if [ -e file1.txt ]; then
       echo "file1.txt ok"
           if [ -e file2.txt ]; then
               echo "file2.txt ok"
               alternative to goto label Z
           else
               alternative to goto label Y
           fi
   else
       echo "file1.txt doesn't exist"
       alternative to goto label X
fi

PD：僅用於傳達想法的基本腳本

批處理是什麼（也應該做 bash）（重要的是避免混淆）：

完整的腳本執行一些命令並創建文件 file1.txt 和 file2.txt。因此，由於腳本很長並且可以在某些時候被中斷，我想要的是從它被中斷的地方開始腳本。這就是驗證的用途：

• 如果 file1.txt 存在 (Y)，則腳本已經創建它，並繼續檢查 file2.txt (Z) 是否存在（腳本的另一部分）。
• 如果 file2.txt 存在（Z），則表示命令從該點開始
• 如果 file2.txt (Z) 不存在，但 file1.txt (Y) 存在，則意味著腳本在創建 file1.txt (Y) 和 file2.txt (Z) 之間的某處被中斷，則它從 file1 開始。 txt (Y)
• 如果 file1.txt (Y) 和 file2.txt (Z) 都不存在，那麼我必須從腳本 (X) 的開頭開始

在確切知道您的批處理腳本應該做什麼之後，我將從簡化它開始：

@echo off
if exist "file1.txt" goto skip_part1
run the script from the beginning and file1.txt and file2.txt are created and the rest of the script is executed
:skip_part1
if exist "file2.txt" goto skip_part2
run the commands to file1.txt and run the rest of the script
:skip_part2
run the commands to file2.txt and run the rest of the script

可以等效地寫為：

@echo off
if not exist "file1.txt" (
 run the script from the beginning and file1.txt and file2.txt are created and the rest of the script is executed
)
if not exist "file2.txt" (
 run the commands to file1.txt and run the rest of the script
)
run the commands to file2.txt and run the rest of the script

這可以直接翻譯成以下 bash 腳本：

#!/bin/bash
if [ ! -e file1.txt ]; then
 run the script from the beginning and file1.txt and file2.txt are created and the rest of the script is executed
fi
if [ ! -e file2.txt ]; then
 run the commands to file1.txt and run the rest of the script
fi
run the commands to file2.txt and run the rest of the script

引用自：https://unix.stackexchange.com/questions/657941