D: How do I pipe (|) through three programs using std.process?

[BoQsc]

On Windows:

While trying to use `spawnshell` I discovered that I can not use 
any alphabetical letters inside the `spawnProcess([Find, 
"Hello"])` it all works when they are numerical `[Find, "6515"]`.

As of recent testing `[Find, "df123"]` also is acceptable,
but not when letter is on the right `[Find, "df123d"]`

Unable to figure why this is the case and how to resolve it.

**Working example without problems:**

```
import std.stdio;
import std.process;

version (Windows) { enum Find = "find"; }
version (Posix) { enum Find = "grep"; }

int main (string [] args)
{
    auto p1 = pipe;
    auto p2 = pipe;

    auto pid1 = spawnShell("echo 123", stdin, p1.writeEnd);
    auto pid2 = spawnProcess([Find, "123"], p1.readEnd, 
p2.writeEnd);
    auto pid3 = spawnProcess([Find, "123"], p2.readEnd, stdout);
    wait (pid1);
    wait (pid2);
    wait (pid3);
    return 0;
}
```

**Output:**
```
123

```


**Immediate issue if alphabetical letters are used:**

```
import std.stdio;
import std.process;

version (Windows) { enum Find = "find"; }
version (Posix) { enum Find = "grep"; }

int main (string [] args)
{
    auto p1 = pipe;
    auto p2 = pipe;

    auto pid1 = spawnShell("echo HelloWorld", stdin, p1.writeEnd);
    auto pid2 = spawnProcess([Find, "HelloWorld"], p1.readEnd, 
p2.writeEnd);
    auto pid3 = spawnProcess([Find, "HelloWorld"], p2.readEnd, 
stdout);
    wait (pid1);
    wait (pid2);
    wait (pid3);
    return 0;
}
```
**Output:**
```
FIND: Parameter format not correct
FIND: Parameter format not correct
The process tried to write to a nonexistent pipe.
```