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digitalmars.D.learn - pipeProcess not returning immediately

reply Johnson Jones <JJ Dynomite.com> writes:
I am running ffplay.exe and my application does not return 
immediately from pipeProcess. I have to close ffplay for my 
program to continue execution.

pipeProcess is suppose to return immediately/run asynchronously, 
and it does with ffmpeg or other programs that return. (which I 
do not know if it is returning immediately or not on those 
because they execute so quickly)

But I have a feeling it is not running asynchronously at all. Any 
ideas? This is on windows and simply calling pipeProcess directly 
with a simple "ffplay filename" example.

ffplay opens up a window showing the spectrogram while the file 
is playing. After I close it out, my app then does what it is 
suppose to. This suggests the pipeProcess is not running 
asynchronously.

		void ExecuteCommand(T...)(T args)
		{
			foreach(t; AliasSeq!T)
				static assert(is(t == string), 
typeof(this).stringof~":"~__PRETTY_FUNCTION__~" requires string 
arguments!");

			pipes = pipeProcess([args[0], (AliasSeq!args)[1..$]], 
Redirect.stdout);
}

call it like

ExecuteCommand("ffplay.exe", "test.wav");
Aug 25
parent reply user1234 <user1234 12.hu> writes:
On Saturday, 26 August 2017 at 01:13:35 UTC, Johnson Jones wrote:
 I am running ffplay.exe and my application does not return 
 immediately from pipeProcess. I have to close ffplay for my 
 program to continue execution.
No process is asynchronous in std.process. If you don't want to block your program then wrap it in a thread that checks periodically for termination.
Aug 25
parent FoxyBrown <Foxy Brown.IPT> writes:
On Saturday, 26 August 2017 at 06:24:26 UTC, user1234 wrote:
 On Saturday, 26 August 2017 at 01:13:35 UTC, Johnson Jones 
 wrote:
 I am running ffplay.exe and my application does not return 
 immediately from pipeProcess. I have to close ffplay for my 
 program to continue execution.
No process is asynchronous in std.process. If you don't want to block your program then wrap it in a thread that checks periodically for termination.
Either you are wrong or the docks are wrong: https://dlang.org/phobos/std_process.html pipeProcess also spawns a child process which runs in **parallel** with its parent. However, instead of taking arbitrary streams, it automatically creates a set of pipes that allow the parent to communicate with the child through the child's standard input, output, and/or error streams. This function corresponds roughly to C's popen function.
Aug 26