bash 将 grep 计数分配给变量

Assign grep count to variable

提问by JavaSheriff

How to assign the result of

如何分配结果

grep -c "some text" /tmp/somePath

into variable so I can echo it.

变成变量，所以我可以回应它。

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

I also tried:

我也试过：

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

But I keep getting: command not found.

但我不断得到：command not found。

回答by that other guy

To assign the output of a command, use var=$(cmd)(as shellcheckautomatically tells you if you paste your script there).

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}"

回答by JavaSheriff

Found the issue
Its the assignment, this will work:

发现问题
它的分配，这将工作：

some_var=$(command)

While this won't work:

虽然这行不通：

some_var = $(command)

Thank you for your help! I will accept first helpful answer.

感谢您的帮助！我会接受第一个有用的答案。

回答by Lev Levitsky

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

From man bash:

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.