> -----Message d'origine----- > De : fpc-pascal-boun...@lists.freepascal.org [mailto:fpc-pascal- > boun...@lists.freepascal.org] De la part de Michael Van Canneyt > Envoyé : mercredi 25 mars 2015 09:54 > À : FPC-Pascal users discussions > Objet : Re: [fpc-pascal] TProcess does not work in Windows XP > > > > On Wed, 25 Mar 2015, Antonio Sanguigni wrote: > > > 2015-03-25 8:41 GMT+01:00 Michael Van Canneyt > <mich...@freepascal.org>: > >>> ---------------------- code --------------- > >>> procedure TBurpClient.Run; > >>> begin > >>> fOurProcess.Options := [poUsePipes] + [poNoConsole]; > >>> fOurProcess.Execute; > >>> while True do > >>> begin > >>> // make sure we have room > >>> fMemStream.SetSize(fBytesRead + READ_BYTES); > >>> > >>> // try reading it > >>> fNumBytes := fOurProcess.Output.Read((fMemStream.Memory + > >>> fBytesRead)^, READ_BYTES); > >>> if fNumBytes > 0 then // All read() calls will block, except the > final > >>> one. > >> > >> > >> I am not sure this is always correct. Various versions of windows > work > >> differently in this regard; > >> zero (0) may be a valid return value. I suggest you check > >> fOurProcess.IsRunning to break the loop. > > > > Thank you, I will try it. But debugging I can see the problem is not > > in the loop. In Windows XP fNumBytes is always zero: > > > > fNumBytes := fOurProcess.Output.Read((fMemStream.Memory + > > fBytesRead)^, READ_BYTES); > > > > so it seems the Read of fOurProcess.Output is not giving the expected > results. > > Read translates directly to a kernel call. > > > > > In Windows 7 it's ok. > > Once more: > Zero is a valid return value for read from a pipe. > > So it can perfectly be that read attempts 50 times returns 0, and only > at > read attempt 51 you get a positive result. > > That is why you must check isRunning, and not rely on the return value > of readbytes.
It could also be due to the problem we detected in fpmkunit: If the stderr is a separate pipe and that pipe is full, the inferior will stop until that pipe is read. See this patch: http://svn.freepascal.org/cgi-bin/viewvc.cgi/trunk/packages/fcl-process/src/ process.pp?r1=29107&r2=29303 Could the difference between Windows 7 and Windows XP be related to different amount to stderr pipe? Or maybe the internal pipe size is different? In the hope this could be useful, Pierre Muller _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
