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Date:	Sat, 14 Nov 2009 02:19:05 +0000
From:	Dave Korn <dave DOT korn DOT cygwin AT googlemail DOT com>
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Subject:	Re: [BUG] fopen(..., "a") does not seek to end of file until some write operation
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Eric Blake wrote:

> According to Salvador Fandino on 11/13/2009 1:36 PM:

>> Using ftell() after fopen(..., "a") returns 0 even when the file open for appending is not empty. AFAIK, it should return the size of the file.
> 
> Not a bug.  POSIX allows this behavior, and Linux does it as well.  POSIX
> also allows BSD behavior of seeking to the end, although this is less
> friendly to reading back a file opened with fopen(...,"a+").  So portable
> programs can't expect either situation, and you MUST use fseek when
> opening for append if you expect a particular position.

  I'm really confused; aren't you saying that there is exactly no difference
between opening for append and just opening in ordinary r/w mode?  I always
thought the positioning of the write pointer immediately after open was the
only possible difference there could be.

    cheers,
      DaveK

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