<pre><code class="lang-fsharp">open System.IO
open System.Diagnostics

let cmd = new Process()
cmd.StartInfo.FileName &lt;- "ls"
cmd.StartInfo.Arguments &lt;- "-l /usr/bin"
cmd.StartInfo.UseShellExecute &lt;- false
cmd.StartInfo.RedirectStandardOutput &lt;- true

if cmd.Start() |&gt; not then
    failwith "Failed to execute command"

using (new StreamWriter("tmp.txt")) (fun writer -&gt;
    cmd.OutputDataReceived.Add(fun e -&gt; writer.WriteLine(e.Data))
    cmd.BeginOutputReadLine()
    cmd.WaitForExit())
</code></pre>
<p><code>Process.StandardOutput.ReadToEnd</code> can only read 4096 bytes. So if output size is larger than 4096 bytes , we must use the event <a target="_blank" href="https://docs.microsoft.com/en-us/dotnet/api/system.diagnostics.process.outputdatareceived?view=net-6.0">OutputDataReceived</a></p>


```fsharp
open System.IO
open System.Diagnostics

let cmd = new Process()
cmd.StartInfo.FileName <- "ls"
cmd.StartInfo.Arguments <- "-l /usr/bin"
cmd.StartInfo.UseShellExecute <- false
cmd.StartInfo.RedirectStandardOutput <- true

if cmd.Start() |> not then
    failwith "Failed to execute command"

using (new StreamWriter("tmp.txt")) (fun writer ->
    cmd.OutputDataReceived.Add(fun e -> writer.WriteLine(e.Data))
    cmd.BeginOutputReadLine()
    cmd.WaitForExit())
```

`Process.StandardOutput.ReadToEnd` can only read 4096 bytes. So if output size is larger than 4096 bytes , we must use the event [OutputDataReceived](https://docs.microsoft.com/en-us/dotnet/api/system.diagnostics.process.outputdatareceived?view=net-6.0)

Run process and read its output in F#