Bug in Control-d handling?

[Brian Inglis]

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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