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Message-ID: <3f4a8b91-a53f-201d-45e4-d1f469652b6e@SystematicSw.ab.ca>
Date: Mon, 20 Jun 2022 13:22:36 -0600
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Subject: Re: Bug in Control-d handling?
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To: cygwin@cygwin.com
References: <827e2006-2aae-9f7f-9c3f-eef3a7c6e793@cornell.edu>
 <20220620175935.924a49feb13156f1a3cf3da4@nifty.ne.jp>
 <20220620192223.2e0a084a7c093939b1c7c8d6@nifty.ne.jp>
From: Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
Organization: Systematic Software
In-Reply-To: <20220620192223.2e0a084a7c093939b1c7c8d6@nifty.ne.jp>
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On 2022-06-20 04:22, Takashi Yano wrote:
> On Mon, 20 Jun 2022 17:59:35 +0900
> Takashi Yano wrote:
>> Isn't this a bug of newlib? Try following code.
>>
>> #include <stdio.h>
>>
>> int main()
>> {
>> 	printf("%d\n", getchar());
>> 	printf("%d\n", feof(stdin));
>> 	printf("%d\n", getchar());
>> 	return 0;
>> }
>>
>> If you press Ctrl-D at the first getchar(), the second getchar()
>> does not return EOF while it does in linux.
>>
>> The following patch seems to resolve the issue.
>>
>> diff --git a/newlib/libc/stdio/refill.c b/newlib/libc/stdio/refill.c
>> index ccedc7af7..843163b7e 100644
>> --- a/newlib/libc/stdio/refill.c
>> +++ b/newlib/libc/stdio/refill.c
>> @@ -47,11 +47,9 @@ __srefill_r (struct _reent * ptr,
>>   
>>     fp->_r = 0;			/* largely a convenience for callers */
>>   
>> -#ifndef __CYGWIN__
>>     /* SysV does not make this test; take it out for compatibility */
>>     if (fp->_flags & __SEOF)
>>       return EOF;
>> -#endif
>>   
>>     /* if not already reading, have to be reading and writing */
>>     if ((fp->_flags & __SRD) == 0)
>>
>> However, I am not sure what this #ifndef __CYGWIN__ is for.
> 
> Ah, I confirmed that System V (Solaris 11.4) behaves like that.
> Does cygwin aim for System V compatibility???

The emphasis has shifted over the years from Solaris etc. compatibility 
when Sparc desktops were ubiquitous (and I switched from DJGPP to 
Cygwin) to Linux etc. compatibility as PCs displaced RISC boxes.
I think ACLs were the last new feature where Solaris was considered vs 
POSIX.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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