Bash 未使用文本文件输入运行Shell脚本

我正在使用MapperShell脚本解决一些问题。我已经创建了两个文件

mr_test.txt

我们将看到map reduce如何处理单词计数问题。单词计数被认为是map reduce编程的hello world。该程序不会打印hello world，而是提供字数。让我们看看地图在行动中的减少

还有另一个shell脚本，名为

mapper.sh

while read line; do
  for token in $line; do
    if ["$token" = "hello" ]; then 
      echo "hello,1"
    elif ["$token" = "world"]; then 
      echo "world,1"
    fi
  done
done

我希望在这里使用shell脚本打印txt文档中的所有hello和world。 现在我输入以下命令

chmod +x mapper.sh

后来

cat mr_test.txt | ./mapper.sh

我得到的输出是

./mapper.sh: line 5: [hello: command not found
./mapper.sh: line 8: [hello: command not found
./mapper.sh: line 5: $'[everyone,\r': command not found
./mapper.sh: line 8: $'[everyone,\r': command not found
./mapper.sh: line 5: [we: command not found
./mapper.sh: line 8: [we: command not found
./mapper.sh: line 5: [will: command not found
./mapper.sh: line 8: [will: command not found
./mapper.sh: line 5: [see: command not found
./mapper.sh: line 8: [see: command not found
./mapper.sh: line 5: [how: command not found
./mapper.sh: line 8: [how: command not found
./mapper.sh: line 5: [map: command not found
./mapper.sh: line 8: [map: command not found
./mapper.sh: line 5: [reduce: command not found
./mapper.sh: line 8: [reduce: command not found
./mapper.sh: line 5: [works: command not found
./mapper.sh: line 8: [works: command not found
./mapper.sh: line 5: [for: command not found
./mapper.sh: line 8: [for: command not found
./mapper.sh: line 5: [word: command not found
./mapper.sh: line 8: [word: command not found
./mapper.sh: line 5: [count: command not found
./mapper.sh: line 8: [count: command not found
./mapper.sh: line 5: [problem.: command not found
./mapper.sh: line 8: [problem.: command not found
./mapper.sh: line 5: [word: command not found
./mapper.sh: line 8: [word: command not found
./mapper.sh: line 5: [count: command not found
./mapper.sh: line 8: [count: command not found
./mapper.sh: line 5: [is: command not found
./mapper.sh: line 8: [is: command not found
./mapper.sh: line 5: [considered: command not found
./mapper.sh: line 8: [considered: command not found
./mapper.sh: line 5: [as: command not found
./mapper.sh: line 8: [as: command not found
./mapper.sh: line 5: [hello: command not found
./mapper.sh: line 8: [hello: command not found
./mapper.sh: line 5: [world: command not found
./mapper.sh: line 8: [world: command not found
./mapper.sh: line 5: [of: command not found
./mapper.sh: line 8: [of: command not found
./mapper.sh: line 5: [map: command not found
./mapper.sh: line 8: [map: command not found
./mapper.sh: line 5: [reduce: command not found
./mapper.sh: line 8: [reduce: command not found
./mapper.sh: line 5: [programming.: command not found
./mapper.sh: line 8: [programming.: command not found
./mapper.sh: line 5: [this: command not found
./mapper.sh: line 8: [this: command not found
./mapper.sh: line 5: [program: command not found
./mapper.sh: line 8: [program: command not found
./mapper.sh: line 5: [will: command not found
./mapper.sh: line 8: [will: command not found
./mapper.sh: line 5: [not: command not found
./mapper.sh: line 8: [not: command not found
./mapper.sh: line 5: [print: command not found
./mapper.sh: line 8: [print: command not found
./mapper.sh: line 5: [hello: command not found
./mapper.sh: line 8: [hello: command not found
./mapper.sh: line 5: [world: command not found
./mapper.sh: line 8: [world: command not found
./mapper.sh: line 5: [instead: command not found
./mapper.sh: line 8: [instead: command not found
./mapper.sh: line 5: [it: command not found
./mapper.sh: line 8: [it: command not found
./mapper.sh: line 5: [will: command not found
./mapper.sh: line 8: [will: command not found
./mapper.sh: line 5: [give: command not found
./mapper.sh: line 8: [give: command not found
./mapper.sh: line 5: [word: command not found
./mapper.sh: line 8: [word: command not found
./mapper.sh: line 5: [counts.: command not found
./mapper.sh: line 8: [counts.: command not found
./mapper.sh: line 5: [lets: command not found
./mapper.sh: line 8: [lets: command not found
./mapper.sh: line 5: [see: command not found
./mapper.sh: line 8: [see: command not found
./mapper.sh: line 5: [map: command not found
./mapper.sh: line 8: [map: command not found
./mapper.sh: line 5: [reduce: command not found
./mapper.sh: line 8: [reduce: command not found
./mapper.sh: line 5: [in: command not found
./mapper.sh: line 8: [in: command not found
./mapper.sh: line 5: $'[action.\r': command not found
./mapper.sh: line 8: $'[action.\r': command not found

---

我已经检查了很多地方的错误语法，但无法缩小范围，以了解出了什么问题

这应该适合你。Shell对空格很敏感，尤其是“[”周围，它不是方括号，而是条件检查

while read line;
do
        for token in $line
        do
                if [ $token = "hello" ]; then
                        echo "Hello,1"
                elif [ $token = "world" ]; then
                        echo "world,1"
                fi
        done
done

---

为避免“读取行”之间出现空格问题，请使用以下方法：

#!/bin/bash

FILE=$1
CNT=0
while read line; do
    if [[ $line == "hello world" ]]; then
        CNT=$(( $CNT + 1 ))
    fi  
done < $1

echo "File '$1' has $CNT times the 'hello world' phrase"

！/bin/bash
文件=$1
CNT=0
边读边做
如果[[$line==“hello world”]；那么
CNT=$（$CNT+1））
fi
已完成<$1
echo“文件“$1”的$CNT乘以“hello world”短语”

要运行脚本，请将wordfile作为参数传递，如下所示：

---

./mapper.sh mr_test.txt

[

不是shell语法的一部分，而是一个命令。更明显的问题是拼写它

test

（命令

test

和命令

[

之间的唯一区别是

[

要求它的最后一个参数是

]

）

if[“$token”=“hello”]

与

if test“$token”=hello

在语义上是相同的。显然，

if test“$token”=hello

是一个错误，这应该说明为什么

if[“$token”=hello]

是一个错误

请注意，引用规则很重要，可能需要明确指出，

如果测试“$token”

的处理方式与

如果“测试$token”

的处理方式完全相同

对于此特定脚本，最好使用case语句：

while read line; do
  for token in $line; do
    case $token in
    hello) echo hello,1;;
    world) echo world,1;;
    esac
  done
done

---

将脚本放入其中会告诉错误您只读取文本文件，对吗？在这种情况下，只需在文件中键入./mapper.shif语句的语法是

if

命令，括号不是条件语法的一部分（与许多其他语言不同）。单个

[

实际上是

测试

命令（执行

类型[

）。正如您所知，在shell语言中，空格必须分隔命令，因此

if

和

[

命令之间应该有空格，而

之间应该有空格[

和传递给它的参数。cat奖励的无用用法？/mapper.sh[不是一个“条件检查”。它是一个命令。如果拼写为“test”，如果test“$token”=hello；写

，就更清楚了；

考虑

[

进行更好的测试。