digitalmars.D.learn - flush MessageBox

Chris (3/3) Aug 20 2015 Is there a way to flush a thread's message box other than

John Colvin (3/6) Aug 20 2015 flush from inside the thread? You could call receiveTimeout with

Chris (8/15) Aug 21 2015 Yes, from inside the thread. I have a worker thread (with

John Colvin (13/29) Aug 21 2015 void flushMailbox()

Chris (11/41) Aug 21 2015 Wouldn't it be easier to have a library function that can empty

Chris (2/31) Aug 21 2015 Thanks by the way. This does the trick.
John Colvin (3/15) Aug 21 2015 yes, it would be better. Please file an enhancement request:

Chris (3/22) Aug 24 2015 Done.

"Chris" <wendlec tcd.ie> writes:

Is there a way to flush a thread's message box other than 
aborting the thread? MailBox is private:

https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

Aug 20 2015

"John Colvin" <john.loughran.colvin gmail.com> writes:

On Thursday, 20 August 2015 at 15:25:57 UTC, Chris wrote:
 Is there a way to flush a thread's message box other than 
 aborting the thread? MailBox is private:

 https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

flush from inside the thread? You could call receiveTimeout with 
a 0 timer in a loop until it returns false.

Aug 20 2015

"Chris" <wendlec tcd.ie> writes:

On Thursday, 20 August 2015 at 15:57:47 UTC, John Colvin wrote:
 On Thursday, 20 August 2015 at 15:25:57 UTC, Chris wrote:
 Is there a way to flush a thread's message box other than 
 aborting the thread? MailBox is private:

 https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

 flush from inside the thread? You could call receiveTimeout 
 with a 0 timer in a loop until it returns false.

Yes, from inside the thread. I have a worker thread (with 
receiveTimeout) that is started when the program starts and sits 
there waiting for input. I naively thought this was a great idea, 
until I noticed that when input comes fast the mailbox grows and 
the bloody thread won't stop until all the items in the mailbox 
are processed. I was looking for something like `if (abort) { 
mailbox.flush(); }`

Aug 21 2015

"John Colvin" <john.loughran.colvin gmail.com> writes:

On Friday, 21 August 2015 at 10:43:22 UTC, Chris wrote:
 On Thursday, 20 August 2015 at 15:57:47 UTC, John Colvin wrote:
 On Thursday, 20 August 2015 at 15:25:57 UTC, Chris wrote:
 Is there a way to flush a thread's message box other than 
 aborting the thread? MailBox is private:

 https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

 flush from inside the thread? You could call receiveTimeout 
 with a 0 timer in a loop until it returns false.

 Yes, from inside the thread. I have a worker thread (with 
 receiveTimeout) that is started when the program starts and 
 sits there waiting for input. I naively thought this was a 
 great idea, until I noticed that when input comes fast the 
 mailbox grows and the bloody thread won't stop until all the 
 items in the mailbox are processed. I was looking for something 
 like `if (abort) { mailbox.flush(); }`

void flushMailbox()
{
     bool r;
     do
     {
         r = receiveTimeout(Duration.zero, (Variant _){});
     } while(r);
}

You could optimise that to more efficiently deal with the actual 
types you're receiving, instead of making a Variant every time, 
but it's probably not worth it. The compiler might even optimise 
it away anyway.

Aug 21 2015

"Chris" <wendlec tcd.ie> writes:

On Friday, 21 August 2015 at 12:59:09 UTC, John Colvin wrote:
 On Friday, 21 August 2015 at 10:43:22 UTC, Chris wrote:
 On Thursday, 20 August 2015 at 15:57:47 UTC, John Colvin wrote:
 On Thursday, 20 August 2015 at 15:25:57 UTC, Chris wrote:
 Is there a way to flush a thread's message box other than 
 aborting the thread? MailBox is private:

 https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

 flush from inside the thread? You could call receiveTimeout 
 with a 0 timer in a loop until it returns false.

 Yes, from inside the thread. I have a worker thread (with 
 receiveTimeout) that is started when the program starts and 
 sits there waiting for input. I naively thought this was a 
 great idea, until I noticed that when input comes fast the 
 mailbox grows and the bloody thread won't stop until all the 
 items in the mailbox are processed. I was looking for 
 something like `if (abort) { mailbox.flush(); }`

 void flushMailbox()
 {
     bool r;
     do
     {
         r = receiveTimeout(Duration.zero, (Variant _){});
     } while(r);
 }

 You could optimise that to more efficiently deal with the 
 actual types you're receiving, instead of making a Variant 
 every time, but it's probably not worth it. The compiler might 
 even optimise it away anyway.

Wouldn't it be easier to have a library function that can empty 
the mailbox immediately? It's a waste of time to have all items 
in the mailbox crash against a wall, before you can go on as in

[
item1  // cancel
item2  ===> do nothing return;
item3  ===> do nothing return;
]

In parts I find std.concurrency lacking. Simple things sometimes 
need workarounds.

Aug 21 2015

"Chris" <wendlec tcd.ie> writes:

On Friday, 21 August 2015 at 14:35:53 UTC, Chris wrote:
 On Friday, 21 August 2015 at 12:59:09 UTC, John Colvin wrote:
 On Friday, 21 August 2015 at 10:43:22 UTC, Chris wrote:
 On Thursday, 20 August 2015 at 15:57:47 UTC, John Colvin 
 wrote:
 On Thursday, 20 August 2015 at 15:25:57 UTC, Chris wrote:
 Is there a way to flush a thread's message box other than 
 aborting the thread? MailBox is private:

 https://github.com/D-Programming-Language/phobos/blob/master/std/concurrency.d#L1778

 flush from inside the thread? You could call receiveTimeout 
 with a 0 timer in a loop until it returns false.

 Yes, from inside the thread. I have a worker thread (with 
 receiveTimeout) that is started when the program starts and 
 sits there waiting for input. I naively thought this was a 
 great idea, until I noticed that when input comes fast the 
 mailbox grows and the bloody thread won't stop until all the 
 items in the mailbox are processed. I was looking for 
 something like `if (abort) { mailbox.flush(); }`

 void flushMailbox()
 {
     bool r;
     do
     {
         r = receiveTimeout(Duration.zero, (Variant _){});
     } while(r);
 }



Thanks by the way. This does the trick.

Aug 21 2015

"John Colvin" <john.loughran.colvin gmail.com> writes:

On Friday, 21 August 2015 at 14:35:53 UTC, Chris wrote:
 On Friday, 21 August 2015 at 12:59:09 UTC, John Colvin wrote:
 [...]

 Wouldn't it be easier to have a library function that can empty 
 the mailbox immediately? It's a waste of time to have all items 
 in the mailbox crash against a wall, before you can go on as in

 [
 item1  // cancel
 item2  ===> do nothing return;
 item3  ===> do nothing return;
 ]

 In parts I find std.concurrency lacking. Simple things 
 sometimes need workarounds.

yes, it would be better. Please file an enhancement request: 
https://issues.dlang.org

Aug 21 2015

"Chris" <wendlec tcd.ie> writes:

On Friday, 21 August 2015 at 17:05:56 UTC, John Colvin wrote:
 On Friday, 21 August 2015 at 14:35:53 UTC, Chris wrote:
 On Friday, 21 August 2015 at 12:59:09 UTC, John Colvin wrote:
 [...]

 Wouldn't it be easier to have a library function that can 
 empty the mailbox immediately? It's a waste of time to have 
 all items in the mailbox crash against a wall, before you can 
 go on as in

 [
 item1  // cancel
 item2  ===> do nothing return;
 item3  ===> do nothing return;
 ]

 In parts I find std.concurrency lacking. Simple things 
 sometimes need workarounds.

 yes, it would be better. Please file an enhancement request: 
 https://issues.dlang.org

Done.

https://issues.dlang.org/show_bug.cgi?id=14953

Aug 24 2015

D Programming

C/C++ Programming

Other

digitalmars.D.learn - flush MessageBox