If语句语法错误（BASH）[重复]

Question

我正在尝试使用以下脚本获取服务器上某些站点的磁盘使用情况，但每当我尝试运行它时都会收到此错误：

args.sh: line 50: syntax error near unexpected token `fi'
args.sh: line 50: `fi'

我看不到任何语法错误，但我显然做错了什么。谁能告诉我这是怎么回事？

这是我的代码：

#!/bin/bash

prefix="/var/www/html/"
suffix=".example.com"
path="$prefix$1$suffix"
args_length="$#"
paths_array=[]
args_array=("$@")

# If there is one argument, calculate disk usage of given site.
if [ args_length -eq 1];
    then echo "Calculating disk usage..."
    output=$(du -sh $path)
    echo "This site is currently using $output"
    exit 1

# If there are no arguments, calculate disk usage of all sites.
elif [ args_length -lt 1];
    then echo "Calculating disk usage for all sites..."
    # I haven't done this part yet!
    exit 1

# If there is more than one site, calculate their disk usage    
elif [ args_length > 1];
    then echo "Calculating disk usage for selected sites..."    
    #Save arguments to sites_array
    for x in args_array; do
        paths_array[x] = args_array[x]
    done
    #Loop through array, creating paths.
    for i in paths_array; do
        site = paths_array[i]
        paths_array[i] = "$prefix$site$suffix"
    done
    #Print out disk usage for each path in array.
    for y in paths_array; do
        output = $(du -sh $paths_array[y]) 
        echo "This site is currently using $output"
fi

旁注：对于我尚未编写的部分，谁能告诉我应该如何将当前工作目录中所有文件夹的名称保存到数组中？我听说解析“ls”的输出是个坏主意，所以如果有人有的话，我正在寻找一种替代方法。

Answer 1

你所拥有的是真的接近 - 你只是有几个不同的小语法错误在这里发挥作用。

语法错误：

1. 您没有使用done 关闭最后一个for 循环 - 因此fi 出现语法错误：解释器认为它仍在循环中。
2. 您在if 语句中的变量名开头删除了$（例如args_length 与$args_length。结果，bash 将其解释为字符串 - args length - 而不是 args_length 变量的值。
3. 您在= 周围放置了空格。在 bash 中，当您为变量赋值时，= 周围不能有空格。相反，它应该始终是：name="value"。
4. 您在 if 语句中的右括号 (]) 前缺少空格。

此代码有效：

#!/bin/bash

prefix="/var/www/html/"
suffix=".example.com"
path="$prefix$1$suffix"
args_length="$#"
paths_array=[]
args_array=("$@")

# If there is one argument, calculate disk usage of given site.
if [ $args_length -eq 1 ];
    then echo "Calculating disk usage..."
    output=$(du -sh $path)
    echo "This site is currently using $output"
    exit 1

# If there are no arguments, calculate disk usage of all sites.
elif [ $args_length -lt 1 ];
    then echo "Calculating disk usage for all sites..."
    # I haven't done this part yet!
    exit 1

# If there is more than one site, calculate their disk usage    
elif [ $args_length -gt 1 ];
    then echo "Calculating disk usage for selected sites..."    
    #Save arguments to sites_array
    for x in args_array; do
        paths_array[x]=$args_array[x]
    done
    #Loop through array, creating paths.
    for i in paths_array; do
        site=$paths_array[i]
        $paths_array[i]="$prefix$site$suffix"
    done
    #Print out disk usage for each path in array.
    for y in paths_array; do
        output=$(du -sh $paths_array[y]) 
        echo "This site is currently using $output"
    done
fi

哪些输出：

Calculating disk usage for all sites...

bash 中的这些错误非常常见，而且很难确定，所以当它们发生时，只需一步一步地重新阅读您的代码，并尝试了解您遇到的错误。