bash - 将 grep 计数分配给变量

Question

如何分配结果

grep -c "some text" /tmp/somePath

进入变量，以便我可以回显它。

#!/bin/bash
some_var = grep -c "some text" /tmp/somePath
echo "var value is: ${some_var}"

我也试过：

some_var = 'grep -c \"some text\" /tmp/somePath'

但我不断得到：command not found。

Answer 1

要分配命令的输出，请使用var=$(cmd)（因为shellcheck 会自动告诉您是否将脚本粘贴到那里）。

#!/bin/bash
some_var=$(grep -c "some text" /tmp/somePath)
echo "var value is: ${some_var}"

Answer 2

找到问题
它的任务，这将工作：

some_var=$(command)

虽然这不起作用：

some_var = $(command)

谢谢您的帮助！我会接受第一个有用的答案。

Answer 3

some_var=$(grep -c "some text" /tmp/somePath)

来自man bash：

   Command substitution allows the output of a command to replace the com‐
   mand name.  There are two forms:

          $(command)
   or
          `command`

   Bash performs the expansion by executing command and replacing the com‐
   mand substitution with the standard output of  the  command,  with  any
   trailing newlines deleted.