This post https://dlang.org/library/std/process/pipe.html
mentions:
Pipes can, for example, be used for interprocess communication
by spawning a new process and passing one end of the pipe to the
child, while the parent uses the other end. (See also
pipeProcess and pipeShell for an easier way of doing this.)
```
auto p = pipe();
auto outFile = File("D downloads.txt", "w");
auto cpid = spawnProcess(["curl",
"http://dlang.org/download.html";],
stdin, p.writeEnd);
scope(exit) wait(cpid);
auto gpid = spawnProcess(["grep", "-o", `http://\S*\.zip`],
p.readEnd, outFile);
scope(exit) wait(gpid);
```
How am I able to compose the pipes from pipeProcess if I can't
pass in an existing pipe into the function. Eg.
```
auto p = pipeProcess("ls");
auto q = pipeProcess("cat", stdin = p.stdout); //it would be good
to do this or something like it
```
Do I need to manually extract the output from pipes.stdin.readln
and place it in pipes.stdout.writeln?
Or is there an easier way to do this?
Thanks
