Thread overview
How do I create a fileWatcher with an onFileChange event using spawn?
Nov 13
bauss
Nov 13
shuji
August 25

Something like this:


module file_watcher;

import std.concurrency;
import std.file;
import std.signals;
import std.datetime;


void fileWatcher(Tid tid, string filename, int loopSleep) {
	auto modified0 = timeLastModified(filename);

	while (true) {
		modified = timeLastModified(filename);
			
		if (modified > modified0) {
			modified0 = modified;
			//if (onFileChange !is null)
			//    onFileChange(receiver);
		}

		sleep(dur!"msecs"(loopSleep));
	}
}


But I'm not sure how to send the onFiledChange event.


August 28
On 2017-08-25 23:25, Enjoys Math wrote:
> 
> 
> Something like this:
> 
> 
> module file_watcher;
> 
> import std.concurrency;
> import std.file;
> import std.signals;
> import std.datetime;
> 
> 
> void fileWatcher(Tid tid, string filename, int loopSleep) {
>      auto modified0 = timeLastModified(filename);
> 
>      while (true) {
>          modified = timeLastModified(filename);
> 
>          if (modified > modified0) {
>              modified0 = modified;
>              //if (onFileChange !is null)
>              //    onFileChange(receiver);
>          }
> 
>          sleep(dur!"msecs"(loopSleep));
>      }
> }
> 
> 
> But I'm not sure how to send the onFiledChange event.

A delegate perhaps?

Or you can look at any of the existing event driven libraries that do this:

http://code.dlang.org/packages/vibe-core
http://code.dlang.org/packages/libasync

-- 
/Jacob Carlborg
August 28
On Monday, 28 August 2017 at 06:27:20 UTC, Jacob Carlborg wrote:
> On 2017-08-25 23:25, Enjoys Math wrote:
>> 
>> 
>> Something like this:
>> 
>> 
>> module file_watcher;
>> 
>> import std.concurrency;
>> import std.file;
>> import std.signals;
>> import std.datetime;
>> 
>> 
>> void fileWatcher(Tid tid, string filename, int loopSleep) {
>>      auto modified0 = timeLastModified(filename);
>> 
>>      while (true) {
>>          modified = timeLastModified(filename);
>> 
>>          if (modified > modified0) {
>>              modified0 = modified;
>>              //if (onFileChange !is null)
>>              //    onFileChange(receiver);
>>          }
>> 
>>          sleep(dur!"msecs"(loopSleep));
>>      }
>> }
>> 
>> 
>> But I'm not sure how to send the onFiledChange event.
>
> A delegate perhaps?
>
> Or you can look at any of the existing event driven libraries that do this:
>
> http://code.dlang.org/packages/vibe-core
> http://code.dlang.org/packages/libasync

In addition, to avoid polling, it's possible to register yourself to the operating system so it will tell you when a modification on the given file has happened: https://msdn.microsoft.com/en-us/library/aa364417%28VS.85%29.aspx?f=255&MSPPError=-2147217396 http://man7.org/linux/man-pages/man7/inotify.7.html
August 28
On 2017-08-28 08:31, Nemanja Boric wrote:
> On Monday, 28 August 2017 at 06:27:20 UTC, Jacob Carlborg wrote:
>> http://code.dlang.org/packages/vibe-core
>> http://code.dlang.org/packages/libasync
> 
> In addition, to avoid polling, it's possible to register yourself to the operating system so it will tell you when a modification on the given file has happened: https://msdn.microsoft.com/en-us/library/aa364417%28VS.85%29.aspx?f=255&MSPPError=-2147217396 http://man7.org/linux/man-pages/man7/inotify.7.html

That's what the two libraries above provides, in a cross-platform way.

-- 
/Jacob Carlborg
August 28
On Monday, 28 August 2017 at 06:27:20 UTC, Jacob Carlborg wrote:
> On 2017-08-25 23:25, Enjoys Math wrote:
>> 
>> 
>> Something like this:
>> 
>> 
>> module file_watcher;
>> 
>> import std.concurrency;
>> import std.file;
>> import std.signals;
>> import std.datetime;
>> 
>> 
>> void fileWatcher(Tid tid, string filename, int loopSleep) {
>>      auto modified0 = timeLastModified(filename);
>> 
>>      while (true) {
>>          modified = timeLastModified(filename);
>> 
>>          if (modified > modified0) {
>>              modified0 = modified;
>>              //if (onFileChange !is null)
>>              //    onFileChange(receiver);
>>          }
>> 
>>          sleep(dur!"msecs"(loopSleep));
>>      }
>> }
>> 
>> 
>> But I'm not sure how to send the onFiledChange event.
>
> A delegate perhaps?
>
> Or you can look at any of the existing event driven libraries that do this:
>
> http://code.dlang.org/packages/vibe-core
> http://code.dlang.org/packages/libasync

No a plain delegate won't work.  There's something you're not telling me because I've tried delegates.  They have to be shared or something, and that causes a big mess with my code.
November 13
On Friday, 25 August 2017 at 21:25:37 UTC, Enjoys Math wrote:
>
>
> Something like this:
>
>
> module file_watcher;
>
> import std.concurrency;
> import std.file;
> import std.signals;
> import std.datetime;
>
>
> void fileWatcher(Tid tid, string filename, int loopSleep) {
> 	auto modified0 = timeLastModified(filename);
>
> 	while (true) {
> 		modified = timeLastModified(filename);
> 			
> 		if (modified > modified0) {
> 			modified0 = modified;
> 			//if (onFileChange !is null)
> 			//    onFileChange(receiver);
> 		}
>
> 		sleep(dur!"msecs"(loopSleep));
> 	}
> }
>
>
> But I'm not sure how to send the onFiledChange event.

@Nemanja Boric I would not recommend calling those APIs on Windows because they work on entire directories, not suitable for individual files and sometimes  those functions not even work when other programs change the files in a non standard way (that has happened to me before when editing through a text editor)
@Enjoys Math The way I usually deal with this problem is I save the filename, the time and handler function in an associative array and loop through when something changes, this way you can delete, sort, etc on the map when the files are deleted or so.
Hope this helps a little.
November 13
On Monday, 28 August 2017 at 11:25:03 UTC, Jacob Carlborg wrote:
> On 2017-08-28 08:31, Nemanja Boric wrote:
>> On Monday, 28 August 2017 at 06:27:20 UTC, Jacob Carlborg wrote:
>>> http://code.dlang.org/packages/vibe-core
>>> http://code.dlang.org/packages/libasync
>> 
>> In addition, to avoid polling, it's possible to register yourself to the operating system so it will tell you when a modification on the given file has happened: https://msdn.microsoft.com/en-us/library/aa364417%28VS.85%29.aspx?f=255&MSPPError=-2147217396 http://man7.org/linux/man-pages/man7/inotify.7.html
>
> That's what the two libraries above provides, in a cross-platform way.

There's already a dub package for file system watching:

https://code.dlang.org/packages/fswatch