NEED HELP: fread, fwrite, fseek, ftell

[Maarten Litmaath]

itkin at mrspoc.UUCP (Steven M. List) writes:
\...
\	byteswritten = fwrite (outbuf, sizeof (char), bytesread, swabfile);
\...
\	bytesread = fread (inbuf, sizeof (char), sizeof inbuf, swabfile);

RTFM (fopen(3s)):

     When a file is opened for update, both input and output  may
     be done on the resulting stream.  However, output may not be
				       ^^^^^^^^^^^^^^^^^^^^^^^^^^
     directly followed by input without an intervening  fseek [...] :-(
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Solution: insert

	fseek(swabfile, ftell(swabfile), 0);

At first sight this looks like a no-op, but there are some `interesting'
side-effects...
What to do if you f*ck things up? Just put it in the FM: it's a feature!
(Which will live on forever.)
BTW, whom can we sue for this? :-)
-- 
 "If it isn't aesthetically pleasing, |Maarten Litmaath @ VU Amsterdam:
  it's probably wrong." (jim at bilpin)  |maart at cs.vu.nl, mcvax!botter!maart