# SHELL \["powershell", "-Command"\] and quote issues

**URL:** <https://forums.docker.com/t/shell-powershell-command-and-quote-issues/23913>\
**Category:** Docker Desktop\
**Tags:** windows\
**Created:** [October 25, 2016, 10:16pm UTC](https://forums.docker.com/t/shell-powershell-command-and-quote-issues/23913 "2016-10-25T22:16:03Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![awsteele](https://avatars.discourse-cdn.com/v4/letter/a/8edcca/32.png) [@awsteele](https://forums.docker.com/u/awsteele)\
**Post date:** [October 25, 2016, 10:16pm UTC](https://forums.docker.com/t/shell-powershell-command-and-quote-issues/23913/1 "2016-10-25T22:16:03Z")

</div>

So I was very excited to see native Docker support in Windows Server 2016. I created a Dockerfile similar to the following and ran into a bit of trouble:

```auto
# escape=`
FROM microsoft/nanoserver
SHELL ["powershell", "-Command"]

RUN Add-Content C:\path\to\file.txt "This is my message"

```

It exploded ☹ because of the quotes. This is the output:

```auto
docker build .
Sending build context to Docker daemon 2.048 kB
Step 1/3 : FROM microsoft/nanoserver
 ---> e14bc0ecea12
Step 2/3 : SHELL powershell -Command
 ---> Running in 69e4802ba983
 ---> ef2271e9628a
Removing intermediate container 69e4802ba983
Step 3/3 : RUN Add-Content C:\path\to\file.txt "This is my message"
 ---> Running in ed88985731db
Add-Content : A positional parameter cannot be found that accepts argument 
'is'.
At line:1 char:1
+ Add-Content C:\path\to\file.txt This is my message
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo : InvalidArgument: (:) [Add-Content], ParameterBin 
   dingException
    + FullyQualifiedErrorId : PositionalParameterNotFound,Microsoft.PowerShell 
   .Commands.AddContentCommand
 
The command 'powershell -Command Add-Content C:\path\to\file.txt "This is my message"' returned a non-zero code: 1

```

What can be done about this? I can escape the quotes, but it’s ugly and feels like I shouldn’t need to do that. Single quotes aren’t always an option because I’d like to make use of string interpolation.

Any pointers / tips?

**EDIT** : Interestingly, the Dockerfile [reference](https://docs.docker.com/engine/reference/builder/#/shell) for the SHELL command switches from using double quotes to single quotes in its examples. Is this a known issue?

---

<div class="post-metadata">

**Author:** ![awsteele](https://avatars.discourse-cdn.com/v4/letter/a/8edcca/32.png) [@awsteele](https://forums.docker.com/u/awsteele)\
**Post date:** [October 26, 2016, 5:12am UTC](https://forums.docker.com/t/shell-powershell-command-and-quote-issues/23913/2 "2016-10-26T05:12:27Z")

</div>

Some further research / notes that may help: When I compile the following program as `app.exe` and then use `SHELL ["app.exe"]`, everything works: the quotes don’t disappear and the `RUN` command works just fine. But of course this is a hack and it’d be great if I didn’t have to do this.

```auto
using System;
using System.Diagnostics;

namespace ConsoleApplication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var startInfo = new ProcessStartInfo {
                FileName = "powershell.exe",
                Arguments = "-Command - ",
                UseShellExecute = false,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                RedirectStandardInput = true,
            };

            var process = new Process {
                StartInfo = startInfo,
            };

            process.OutputDataReceived += (s, e) => Console.WriteLine(e.Data);
            process.ErrorDataReceived += (s, e) => Console.WriteLine(e.Data);
            process.Start();
            process.BeginOutputReadLine();
            process.BeginErrorReadLine();

            var cmd = Environment.CommandLine.Substring(7);
            var inp = process.StandardInput;
            inp.WriteLine(cmd);
            inp.Close();

            process.WaitForExit();
        }
    }
}

```

---

<div class="post-metadata">

**Author:** ![spencerjohnson627](https://avatars.discourse-cdn.com/v4/letter/s/ba9def/32.png) [@spencerjohnson627](https://forums.docker.com/u/spencerjohnson627)\
**Post date:** [June 19, 2018, 1:49pm UTC](https://forums.docker.com/t/shell-powershell-command-and-quote-issues/23913/3 "2018-06-19T13:49:20Z")

</div>

Use “powershell.exe” instead of “powershell”.