Hello Andrew, It would help if glpsol --write would write a format version descriptor into the first line. Then a reading program can easily check if it can parse the file.
E.g. c File-Format: GLPK MIP 1.0 Best regards Heinrich Schuchardt On 01/21/2017 02:37 PM, Andrew Makhorin wrote: >> -------- Forwarded Message -------- >> From: Morten Welinder <[email protected]> >> To: [email protected] >> Subject: glpsol's --write format changed >> Date: Fri, 20 Jan 2017 08:18:55 -0500 >> >> It looks like the format for "glpsol --write ..." changed in Glpk >> version 4.59, a version >> described as a maintenance release. >> >> I realise that this was probably deliberate. Nevertheless, I would >> like you to think of >> it as a bug. >> >> The effect of such a change is to break programs that interact with >> glpsol. In my case, >> Gnumeric broke when some Linux distribution upgraded Glpk. >> >> Please keep such interactions in mind for future format changes. >> >> I note that neither the new format nor the old one contains any format >> version indication. >> Detection of format is thus inherently an ad hoc affair. >> >> Morten Welinder >> Gnumeric maintainer >> >> > > Thank you for your bug report. > > In my defence I'd like to note that it is quite difficult to design > all aspects of the interface at once. The old format was chosen > temporarily just to provide functionality of write_sol and subsequent > read_sol, and there was no intention to use this old format for > communication between glpk and other application programs. Starting > from glpk 4.60 all api routines use so called "glpk format" (which is > a thoroughly designed unified plain text format based on dimacs format), > and I have no plans to change this format in the future. > > > Andrew Makhorin, > the author and maintainer of glpk > > > > _______________________________________________ > Bug-glpk mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/bug-glpk > _______________________________________________ Bug-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/bug-glpk
