delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2020/07/28/15:52:28

X-Recipient: archive-cygwin AT delorie DOT com
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org E48573857C59
Authentication-Results: sourceware.org;
dmarc=none (p=none dis=none) header.from=bahnhof.se
Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=rabbe AT bahnhof DOT se
X-Virus-Scanned: Debian amavisd-new at bahnhof.se
X-Spam-Score: -2.25
X-Spam-Level:
X-Spam-Status: No, score=-0.6 required=5.0 tests=BAYES_00, BODY_8BITS,
KAM_DMARC_STATUS, KAM_NUMSUBJECT, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_PASS,
TXREP autolearn=ham autolearn_force=no version=3.4.2
Subject: Re: stty -cooked not usable since cygwin-3.1.1-1
To: cygwin AT cygwin DOT com
References: <ad285b65-fed9-e6e5-eb3f-432fadc95daf AT bahnhof DOT se>
<20200113200152 DOT 5243a304d481677c61c12450 AT nifty DOT ne DOT jp>
<12d7cb6e-b900-6780-1d1c-80ed84cc82d5 AT bahnhof DOT se>
<1ea4e90c-7075-39e8-a518-40bc764a5237 AT bahnhof DOT se>
<20200729013848 DOT cf6d4d99464e92d92d346029 AT nifty DOT ne DOT jp>
<d78149b7-b4c8-5619-71ca-f3b70a04fd26 AT towo DOT net>
From: Rabbe Fogelholm <rabbe AT bahnhof DOT se>
Message-ID: <22f2becd-1f2e-5ff8-4999-b34f2fb0bff3@bahnhof.se>
Date: Tue, 28 Jul 2020 21:51:33 +0200
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101
Thunderbird/68.10.0
MIME-Version: 1.0
In-Reply-To: <d78149b7-b4c8-5619-71ca-f3b70a04fd26@towo.net>
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.29
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
<mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
<mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
Errors-To: cygwin-bounces AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces AT cygwin DOT com>
X-MIME-Autoconverted: from base64 to 8bit by delorie.com id 06SJq9sI005256

On 2020-07-28 18:56, Thomas Wolff wrote:
> 
> 
> Am 28.07.2020 um 18:38 schrieb Takashi Yano via Cygwin:
>> On Tue, 28 Jul 2020 15:56:54 +0200
>> Rabbe Fogelholm wrote:
>>> Rabbe Fogelholm wrote:
>>>> Takashi Yano wrote:
>>>>> On Mon, 13 Jan 2020 11:52:43 +0100
>>>>> Rabbe Fogelholm wrote:
>>>>>> I am running a console Java program that is started from a 
>>>>>> shellscript
>>>>>> wrapper. Before invoking Java the wrapper calls `stty -cooked'. 
>>>>>> The Java
>>>>>> program polls the keyboard using System.in.available() and reads
>>>>>> characters immediately using System.in.read(), without waiting for 
>>>>>> the
>>>>>> Enter key to be pressed.
>>>>>>
>>>>>> This way of combining `stty -cooked' and Java has stopped working 
>>>>>> since
>>>>>> version 3.1.1-1 of the Cygwin package. The Java thread that reads the
>>>>>> keyboard hangs until Enter is pressed, which is not desirable.
>>>>>>
>>>>>> I had to downgrade to version 3.0.7-1 to resolve the problem.
>>>>>>
>>>>>> Versioning information:
>>>>>>
>>>>>> java version "1.8.0_202"
>>>>>> Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
>>>>>> Java HotSpot(TM) 64-Bit Server VM (build 25.202-b08, mixed mode)
>>>>>>
>>>>>> OS Name: Microsoft Windows 10 Pro
>>>>>> Version: 10.0.17763 Build 17763
>>>>>> System Type: x64-based PC
>>>>>>
>>>>>> See also the enclosed cygcheck.out.
>>>>>>
>>>>>> To demonstrate the issue I enclose a small Java program that 
>>>>>> should be
>>>>>> able to read single keystrokes when `stty -cooked' is in effect.
>>>>> Does your java program work in command prompt? cygwin 3.1.x uses
>>>>> pseudo console, so the native (non cygwin) program works as if it
>>>>> is executed in command prompt.
>>>>>
>>>> With cygwin 3.1.x I can't find a way to make my program work.
>>>>
>>>> When running from within a Cygwin64 terminal the `stty -cooked' command
>>>> terminates with exit code 0, but the Java program behaves just as if
>>>> `stty -cooked' is not in effect: It does not handle single keystrokes
>>>> immediately.
>>>>
>>>> When running from a Windows command prompt I can execute the stty
>>>> program as \cygwin64\bin\stty. However, when given the '-cooked'
>>>> argument it complains:
>>>> /usr/bin/stty: 'standard input': unable to perform all requested 
>>>> operations
>>>>
>>>> - and here as well the Java program behaves as if `stty -cooked' is not
>>>> in effect.
>>> Some time has passed; I am just curious if anyone may have found a
>>> solution to the "stty -cooked" issue. With cygwin-3.0.* it was possible
>>> to have a Java program act on single keystrokes, with cygwin-3.1 I don't
>>> know how to do it. Any ideas welcome!
>> Solution 1:
>> Redesign your java program using JNA with kbhit()/getch() instead of
>> System.in.available()/System.in.read().
>>
>> Solution 2:
>> Add SetConsoleMode() call with ENABLE_LINE_INPUT flag cleared using JNA.
> Couldn't cygwin clear this flag when it sets up ConPTY while the pty is 
> in raw mode?
> Thomas
> 
>>
>> Solution 3:
>> Use a wrappwer instead of stty such as:
>>
>> #include <stdio.h>
>> #include <unistd.h>
>> #include <termios.h>
>> #include <string.h>
>> #include <pthread.h>
>> #include <sys/wait.h>
>>
>> void *fwd(void *param)
>> {
>>      FILE *f = (FILE *) param;
>>      char buf[128];
>>      int len;
>>      while (1) {
>>          if ((len = read(0, buf, sizeof(buf))) <= 0) break;
>>          if (write(fileno(f), buf, len) < len) break;
>>      }
>>      return NULL;
>> }
>>
>> int main(int argc, char *argv[])
>> {
>>      FILE *f;
>>      int i;
>>      pthread_t th;
>>      struct termios t, t_orig;
>>      char cmd[1024] = {0, };
>>      if (argc < 2) return 0;
>>      for (i = 1; i < argc && strlen(cmd)+strlen(argv[i]) < 
>> sizeof(cmd)-2; i++) {
>>          sprintf(cmd + strlen(cmd), (i>1)?" %s":"%s", argv[i]);
>>      }
>>      f = popen(cmd, "w");
>>      tcgetattr(0, &t_orig);
>>      t = t_orig;
>>      cfmakeraw(&t);
>>      tcsetattr(0, TCSANOW, &t);
>>      pthread_create(&th, NULL, fwd, f);
>>      wait(NULL);
>>      tcsetattr(0, TCSANOW, &t_orig);
>>      pclose(f);
>>      return 0;
>> }
>>
> 
> 
Thanks Takashi for suggesting many ways to solve this! The C wrapper
solution looks quite powerful.

Meanwhile it has occurred to me that bash itself can provide a
workaround. Since I start the Java console application from a bash
wrapper already, I have now changed it so that it does something like
this:

(while true; do read -s -r -N 1 Key; echo "$Key"; done) | java ...

With these options to 'read' I get action on every keystroke, and the
Java program gets its input as terminated length-1 lines.
--
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019