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Today's Topics:
1. forkIO and signal handlers (Michael Litchard)
2. Re: forkIO and signal handlers (Michael Litchard)
3. Re: forkIO and signal handlers (Brandon Allbery)
4. Re: forkIO and signal handlers (Michael Litchard)
5. Re: forkIO and signal handlers (Michael Litchard)
6. Re: forkIO and signal handlers (David McBride)
7. Attoparsec and multiline comments (Alexander.Vladislav.Popov )
----------------------------------------------------------------------
Message: 1
Date: Fri, 9 Sep 2011 12:06:40 -0700
From: Michael Litchard <mich...@schmong.org>
Subject: [Haskell-beginners] forkIO and signal handlers
To: beginners@haskell.org
Message-ID:
<CAEzeKYpRBHHZA=ohzxn-fw+el6dhaugunmzbzbfs1vxwuor...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
I am trying to use installHandler with forkIO.
I'd like to fork a process in Main when a signal is caught, having
trouble with the types and I'm sure there is a convention I'm not
familiar with.
Could I see an example of how this is done?
------------------------------
Message: 2
Date: Fri, 9 Sep 2011 12:35:56 -0700
From: Michael Litchard <mich...@schmong.org>
Subject: Re: [Haskell-beginners] forkIO and signal handlers
To: Tim Perry <tim.pe...@lifetime.oregonstate.edu>
Cc: "beginners@haskell.org" <beginners@haskell.org>
Message-ID:
<caezekyrqcz7dwhzy-ofq8_zxl9ozk-rdy0puf2wrartyuws...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Thanks for the reply. The problem isn't signal handling, nor is it
using forkIO. It's using both of them together.
On Fri, Sep 9, 2011 at 12:14 PM, Tim Perry
<tim.pe...@lifetime.oregonstate.edu> wrote:
> There is an example of forking processes in the "Real World Haskell" book in
> chapter 20 - Systems Programming.
> http://book.realworldhaskell.org/read/systems-programming-in-haskell.html
>
> Unfortunately I don't think it covers catching signals. I hope this helps.
> Tim
> ________________________________
> From: Michael Litchard <mich...@schmong.org>
> To: beginners@haskell.org
> Sent: Friday, September 9, 2011 12:06 PM
> Subject: [Haskell-beginners] forkIO and signal handlers
>
> I am trying to use installHandler with forkIO.
> I'd like to fork a process in Main when a signal is caught, having
> trouble with the types and I'm sure there is a convention I'm not
> familiar with.
> Could I see an example of how this is done?
>
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://www.haskell.org/mailman/listinfo/beginners
>
>
>
------------------------------
Message: 3
Date: Fri, 9 Sep 2011 15:46:19 -0400
From: Brandon Allbery <allber...@gmail.com>
Subject: Re: [Haskell-beginners] forkIO and signal handlers
To: Michael Litchard <mich...@schmong.org>
Cc: Tim Perry <tim.pe...@lifetime.oregonstate.edu>,
"beginners@haskell.org" <beginners@haskell.org>
Message-ID:
<cakfcl4u73unpsmnmgl2kom8c5-tzlzhtyff2kb79hljbz8g...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
On Fri, Sep 9, 2011 at 15:35, Michael Litchard <mich...@schmong.org> wrote:
> Thanks for the reply. The problem isn't signal handling, nor is it
> using forkIO. It's using both of them together.
>
I think you'll have to provide an example of what you're trying to do and
the error message you get.
--
brandon s allbery allber...@gmail.com
wandering unix systems administrator (available) (412) 475-9364 vm/sms
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Message: 4
Date: Fri, 9 Sep 2011 12:53:27 -0700
From: Michael Litchard <mich...@schmong.org>
Subject: Re: [Haskell-beginners] forkIO and signal handlers
To: Brandon Allbery <allber...@gmail.com>
Cc: Tim Perry <tim.pe...@lifetime.oregonstate.edu>,
"beginners@haskell.org" <beginners@haskell.org>
Message-ID:
<caezekyolchposmxkad7ghbxsr08lmzw2bixhzqjsaddntfm...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Here's the error message. The problem is clear, not sure what to do
about it. My broken code should show my intent though.
> main :: IO ()
> main = do
> let world = (newEmptyTMVar :: ProcessState)
> let jCount = (newEmptyTMVar :: JobCount)
> installHandler userDefinedSignal1 (forkIO $ Catch $ worldHandler world
> jCount) Nothing
> sequence_ $ repeat $ worldCheck
I'd like to fork in Main. Right now I'm forking in worldHandler. If
that's what I have to do, then I'll just move on. But I'd like to keep
the forkIO call in Main if possible.
On Fri, Sep 9, 2011 at 12:46 PM, Brandon Allbery <allber...@gmail.com> wrote:
> On Fri, Sep 9, 2011 at 15:35, Michael Litchard <mich...@schmong.org> wrote:
>>
>> Thanks for the reply. The problem isn't signal handling, nor is it
>> using forkIO. It's using both of them together.
>
> I think you'll have to provide an example of what you're trying to do and
> the error message you get.
> --
> brandon s allbery ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?allber...@gmail.com
> wandering unix systems administrator (available) ? ? (412) 475-9364 vm/sms
>
>
------------------------------
Message: 5
Date: Fri, 9 Sep 2011 12:54:21 -0700
From: Michael Litchard <mich...@schmong.org>
Subject: Re: [Haskell-beginners] forkIO and signal handlers
To: Brandon Allbery <allber...@gmail.com>
Cc: Tim Perry <tim.pe...@lifetime.oregonstate.edu>,
"beginners@haskell.org" <beginners@haskell.org>
Message-ID:
<caezekyrdujvq3yanwhusffhblgp3dl4fmhrqw8ny37fyxsb...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
forgot to paste in the error message, oops
copy_take.lhs:48:51:
Couldn't match expected type `IO ()' with actual type `Handler'
In the second argument of `($)', namely
`Catch $ worldHandler world jCount'
In the second argument of `installHandler', namely
`(forkIO $ Catch $ worldHandler world jCount)'
In a stmt of a 'do' expression:
installHandler
userDefinedSignal1
(forkIO $ Catch $ worldHandler world jCount)
Nothing
Failed, modules loaded:
On Fri, Sep 9, 2011 at 12:53 PM, Michael Litchard <mich...@schmong.org> wrote:
> Here's the error message. The problem is clear, not sure what to do
> about it. My broken code should show my intent though.
>
>> main :: IO ()
>> main = do
>> ? ? let world = (newEmptyTMVar :: ProcessState)
>> ? ? let jCount = (newEmptyTMVar :: JobCount)
>> ? ? installHandler userDefinedSignal1 (forkIO $ Catch $ worldHandler world
>> jCount) Nothing
>> ? ? sequence_ $ repeat $ worldCheck
>
> I'd like to fork in Main. Right now I'm forking in worldHandler. If
> that's what I have to do, then I'll just move on. But I'd like to keep
> the forkIO call in Main if possible.
>
>
> On Fri, Sep 9, 2011 at 12:46 PM, Brandon Allbery <allber...@gmail.com> wrote:
>> On Fri, Sep 9, 2011 at 15:35, Michael Litchard <mich...@schmong.org> wrote:
>>>
>>> Thanks for the reply. The problem isn't signal handling, nor is it
>>> using forkIO. It's using both of them together.
>>
>> I think you'll have to provide an example of what you're trying to do and
>> the error message you get.
>> --
>> brandon s allbery ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?allber...@gmail.com
>> wandering unix systems administrator (available) ? ? (412) 475-9364 vm/sms
>>
>>
>
------------------------------
Message: 6
Date: Fri, 9 Sep 2011 16:09:37 -0400
From: David McBride <dmcbr...@neondsl.com>
Subject: Re: [Haskell-beginners] forkIO and signal handlers
To: Michael Litchard <mich...@schmong.org>
Cc: Tim Perry <tim.pe...@lifetime.oregonstate.edu>,
"beginners@haskell.org" <beginners@haskell.org>
Message-ID:
<CAN+Tr43KHjxf6CNcPqR==0aw6fexkypyq6qqww0zvawu4xw...@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Handler is not IO (), it is a handler. Try this:
installHandler userDefinedSignal1 (Catch (forkIO (worldHandler world
jCount) >> return ())) Nothing
On Fri, Sep 9, 2011 at 3:54 PM, Michael Litchard <mich...@schmong.org> wrote:
> forgot to paste in the error message, oops
>
> copy_take.lhs:48:51:
> ? ?Couldn't match expected type `IO ()' with actual type `Handler'
> ? ?In the second argument of `($)', namely
> ? ? ?`Catch $ worldHandler world jCount'
> ? ?In the second argument of `installHandler', namely
> ? ? ?`(forkIO $ Catch $ worldHandler world jCount)'
> ? ?In a stmt of a 'do' expression:
> ? ? ? ?installHandler
> ? ? ? ? ?userDefinedSignal1
> ? ? ? ? ?(forkIO $ Catch $ worldHandler world jCount)
> ? ? ? ? ?Nothing
> Failed, modules loaded:
>
> On Fri, Sep 9, 2011 at 12:53 PM, Michael Litchard <mich...@schmong.org> wrote:
>> Here's the error message. The problem is clear, not sure what to do
>> about it. My broken code should show my intent though.
>>
>>> main :: IO ()
>>> main = do
>>> ? ? let world = (newEmptyTMVar :: ProcessState)
>>> ? ? let jCount = (newEmptyTMVar :: JobCount)
>>> ? ? installHandler userDefinedSignal1 (forkIO $ Catch $ worldHandler world
>>> jCount) Nothing
>>> ? ? sequence_ $ repeat $ worldCheck
>>
>> I'd like to fork in Main. Right now I'm forking in worldHandler. If
>> that's what I have to do, then I'll just move on. But I'd like to keep
>> the forkIO call in Main if possible.
>>
>>
>> On Fri, Sep 9, 2011 at 12:46 PM, Brandon Allbery <allber...@gmail.com> wrote:
>>> On Fri, Sep 9, 2011 at 15:35, Michael Litchard <mich...@schmong.org> wrote:
>>>>
>>>> Thanks for the reply. The problem isn't signal handling, nor is it
>>>> using forkIO. It's using both of them together.
>>>
>>> I think you'll have to provide an example of what you're trying to do and
>>> the error message you get.
>>> --
>>> brandon s allbery ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?allber...@gmail.com
>>> wandering unix systems administrator (available) ? ? (412) 475-9364 vm/sms
>>>
>>>
>>
>
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://www.haskell.org/mailman/listinfo/beginners
>
------------------------------
Message: 7
Date: Sat, 10 Sep 2011 14:05:56 +0600
From: "Alexander.Vladislav.Popov "
<alexander.vladislav.po...@gmail.com>
Subject: [Haskell-beginners] Attoparsec and multiline comments
To: beginners@haskell.org
Message-ID:
<calpbq9au8cd1pur-jhgomhmsll1tf-rs27a3puqtbxp3a6n...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Dear haskellers,
Help me to parse multiline comments (like /* ... */ or even like /*- ...
-*/) using attoparsec.
Thanks in advance, Alexander.
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