英文:
How to use a variable from a block of code in the filename the output is redirected to?
问题
I have a shell script of which I want to capture the output using a block of code (docs).
Additionally I want to use the value of a variable from that block of code in the filename I write the output to, unfortunately that is not working.
How can I re-use the variable from a block of code in the filename?
最小示例
这是一个虚拟脚本，展示了我想要做的事情。我使用的是 GNU bash, version 5.0.17：
{
v=1
echo $v
} >> output-$v.log 2>&1
我设置了一个变量，运行一些命令，并希望将stdout和stderr存储在一个带有该变量的名称的文件中（在这种情况下是 output-1.log）。
然而，这会写出一个名为 output-.log 的文件，就好像 $v 变量不存在一样。
我尝试过的事情
如果我在代码块后面添加一个分号 ;：
{
v=1
echo $v
}; >> output-$v.log 2>&1
则会创建文件 output-1.log，但它保持为空。
英文:
I have a shell script of which I want to capture the output using a block of code (docs).
Additionally I want to use the value of a variable from that block of code in the filename I write the output to, unfortunately that is not working.
How can I re-use the variable from a block of code in the filename?
Minimum example
This is a dummy script showing what I'm trying to do. I have GNU bash, version 5.0.17:
{
v=1
echo $v
} >> output-$v.log 2>&1
I set a variable, run some command and want to store the stdout and stderr in a file that has the variable in it's name (output-1.log in this case).
However, this writes out a file output-.log as if the $v variable does not exist.
What I've tried
If I add a semicolon ; after the block of code:
{
v=1
echo $v
}; >> output-$v.log 2>&1
The file output-1.log is created, but it remains empty
答案1
得分: 1
初始化变量后设置重定向：
v=1
{
echo $v
} >> output-$v.log 2>&1
英文:
Initialize the variable before setting up the redirection:
v=1
{
echo $v
} >> output-$v.log 2>&1
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