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Mail Archives: cygwin/2009/11/13/15:41:26

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Date: Fri, 13 Nov 2009 13:41:14 -0700
From: Eric Blake <ebb9 AT byu DOT net>
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To: cygwin AT cygwin DOT com, sfandino AT yahoo DOT com
Subject: Re: [BUG] fopen(..., "a") does not seek to end of file until some write operation
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According to Salvador Fandino on 11/13/2009 1:36 PM:
> Hii
> 
> 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.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9 AT byu DOT net
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