• Andrew Edwards (63/63) Sep 17 2014 The script below is borrowed form a unit test in core.thread and
• Flamencofantasy (3/66) Sep 17 2014 if (++count >= fibs.length)...
• Kagamin (2/2) Sep 17 2014 and
• Kagamin (2/2) Sep 17 2014 fibs ~= new TestFiber(entry);
• Andrew Edwards (2/4) Sep 17 2014 Kagamin/Flamencofantasy, thank you very much.
• Vladimir Panteleev (16/20) Sep 17 2014 Perhaps this example is oversimplified, but fibers won't help in

Andrew Edwards <ridimz yahoo.com> writes:

The script below is borrowed form a unit test in core.thread and 
modified slightly. If fails with "segmentation fault: 11" but I'm not 
sure why.

Basically what I'm trying to do is to transact on every file in give 
directory at the same time exact time.

In this exam, I'm removing the file/directory but that's just a test to 
see if I could get it to work.

Guidance is requested and appreciated.

Thanks,
Andrew

---------------------------------
import core.thread;
import std.process;
import std.file;
import std.stdio;

void main(string[] args)
{
	auto f = args[1];
	deleteWithFibers(f);
}

class TestFiber : Fiber
{
	string file;

	this(string file)
	{
		this.file = file;
		super(&run);
	}

	void run()
	{
		while (file.exists) {
			if (file.isFile)
				file.remove;
			else if (file.isDir)
				file.rmdir;
			Fiber.yield();
		}
	}
}

void deleteWithFibers(string dir)
{
	auto fibs = new TestFiber[100];
	
	int count = 0;
	foreach (entry; dirEntries(dir, SpanMode.depth))
	{
		fibs[count] = new TestFiber(entry);

		if (++count > fibs.length)
			fibs.length *= 2;
	}

	fibs.length = count+1;

	bool cont;
	do {
		cont = false;
		foreach(fib; fibs) {
			if (fib.state == Fiber.State.HOLD)
			{
				fib.call();
				cont |= fib.state != Fiber.State.TERM;
			}
		}
	} while (cont);
}

"Flamencofantasy" <Flamencofantasy gmail.com> writes:

if (++count >= fibs.length)...


On Wednesday, 17 September 2014 at 10:00:49 UTC, Andrew Edwards
wrote:
 The script below is borrowed form a unit test in core.thread 
 and modified slightly. If fails with "segmentation fault: 11" 
 but I'm not sure why.

 Basically what I'm trying to do is to transact on every file in 
 give directory at the same time exact time.

 In this exam, I'm removing the file/directory but that's just a 
 test to see if I could get it to work.

 Guidance is requested and appreciated.

 Thanks,
 Andrew

 ---------------------------------
 import core.thread;
 import std.process;
 import std.file;
 import std.stdio;

 void main(string[] args)
 {
 	auto f = args[1];
 	deleteWithFibers(f);
 }

 class TestFiber : Fiber
 {
 	string file;

 	this(string file)
 	{
 		this.file = file;
 		super(&run);
 	}

 	void run()
 	{
 		while (file.exists) {
 			if (file.isFile)
 				file.remove;
 			else if (file.isDir)
 				file.rmdir;
 			Fiber.yield();
 		}
 	}
 }

 void deleteWithFibers(string dir)
 {
 	auto fibs = new TestFiber[100];
 	
 	int count = 0;
 	foreach (entry; dirEntries(dir, SpanMode.depth))
 	{
 		fibs[count] = new TestFiber(entry);

 		if (++count > fibs.length)
 			fibs.length *= 2;
 	}

 	fibs.length = count+1;

 	bool cont;
 	do {
 		cont = false;
 		foreach(fib; fibs) {
 			if (fib.state == Fiber.State.HOLD)
 			{
 				fib.call();
 				cont |= fib.state != Fiber.State.TERM;
 			}
 		}
 	} while (cont);
 }

"Kagamin" <spam here.lot> writes:

and
fibs.length = count;

"Kagamin" <spam here.lot> writes:

fibs ~= new TestFiber(entry);
should just work without accounting for number of items

Andrew Edwards <ridimz yahoo.com> writes:

On 9/17/14, 9:43 PM, Kagamin wrote:
 fibs ~= new TestFiber(entry);
 should just work without accounting for number of items


Kagamin/Flamencofantasy, thank you very much.

"Vladimir Panteleev" <vladimir thecybershadow.net> writes:

On Wednesday, 17 September 2014 at 10:00:49 UTC, Andrew Edwards 
wrote:
 Basically what I'm trying to do is to transact on every file in 
 give directory at the same time exact time.

 In this exam, I'm removing the file/directory but that's just a 
 test to see if I could get it to work.

Perhaps this example is oversimplified, but fibers won't help in 
doing some operation at the exact same time. They will still run 
sequentially, on a single CPU, as if no threads/fibers were used.

I don't think there is a way to perform an operation in a truly 
atomic way on a directory or group of files simultaneously, 
without using the operating system's transactional filesystem 
capabilities, and those don't seem to be commonly available 
except on Windows (and even there transactional NTFS is 
deprecated). An alternative would be to lock all files before 
operating on them (thus causing other processes to fail when 
attempting to access to them, instead of corrupting data), or to 
operate on a private copy of the directory, and then swap it with 
the live copy (although swapping a directory atomically is also 
not possible without using symbolic links).