[metapost] mpost returns 1 on successful run?

[Norbert Preining]

Hi Taco,

on the Debian side we got a bug report that with the switch from 
TL2007 mpost to TL2009 mpost the same file suddenly makes mpost
return 1 (failure in shell) instead of 0.

On Do, 24 Dez 2009, Stéphane Glondu wrote:
> This is because of mpost. With the attached file, mpost exists with code
> 1; however, I don't see any error:
> 
> root at korell:/tmp# mpost -interaction="nonstopmode" img_doc.mp end
> This is MetaPost, version 1.208 (kpathsea version 5.0.0)
> (./img_doc.mp (/usr/share/texmf/metapost/context/base/mp-tool.mp)
> (/usr/share/texmf/metapost/context/base/mp-spec.mp) [19] [18] [17] [16] [15]
> [14] [13] [12] [11] [10] [9] [8] [7] [6] [5] [4] [3] [2] [1])
> (see the transcript file for additional information)
> 19 output files written: img_doc.1 .. img_doc.19
> Transcript written on img_doc.log.
> root at korell:/tmp# echo $?
> 1
> 
> The version in testing exits with code 0 on the same file.

Version in testing is 2007.

It turned out that the the following line
	tracingchoices := 1;
seems to made the difference. When I comment that mpost returns 0,
otherwise on. The following minimal mp file exhibits this point:

tracingchoices := 1;
beginfig(1)
  path pathb ;
  pathb = ((0, 0) .. (40, 25));
endfig;
end.

With tracingchoices == 1 mpost returns 1, otherwise 0.

Simple question: Is that intended or a bug? I checked the current
mpman but there is nothing mentioned about return values around
the tracing* pages.

Best wishes

Norbert

------------------------------------------------------------------------
Norbert Preining            preining@{jaist.ac.jp, logic.at, debian.org}
JAIST, Japan            TU Wien, Austria           Debian TeX Task Force
DSA: 0x09C5B094   fp: 14DF 2E6C 0307 BE6D AD76  A9C0 D2BF 4AA3 09C5 B094
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