Date: Wed, 25 Jan 1995 22:35:17 MST From: steve@khoros.unm.edu (Steven Jorgensen) To: questions@FreeBSD.org Subject: possible fopen/fclose bug? Message-ID: <9501260535.AA25049@zen.khoros.unm.edu>
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While porting the Khoros imake system to freebsd 2.0, I noticed that the Makefiles that our version of imake were generating had garbage at the end of the file. Upon further investigation, it became appearent that the problem was in the fact that imake does some post processing on the Makefile by opening the file w+. This allows it to read the Makefile while writing out the modified information to the same file. (Seems kind of dangerous to me, but then I didn't write imake :^) Anyway, the problem is that it closes the file where it stopped reading instead of where it stopped writing, so garbage appears at the end. This is fixed by inserting an explicit ftruncate call right before closing the file. Since this ftruncate is not necessary on the other architectures we support, I was wondering if this is a bug in freebsd's fclose, or whether or not it is an undefined action that we've just been lucky with before this.. :^) Steve -- ------------------------------------------------------------- Steven Jorgensen | Khoral Research Inc. steve@khoros.unm.edu | 6001 Indian School, Suite 200 (505) 837-6500 | Albuquerque, NM 87110 ------------------------+------------------------------------ This Space for Rent. | URL: http://www.khoros.unm.edu/ -------------------------------------------------------------
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