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旧 2009-05-07, 04:11 PM   #1
yang686526
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默认 【转帖】some Files Wont Write

some files won't write
some files won't write
there are a number of files that i need to run for my process that generate errors when i attempt to write them out. as far as i am able to tell, there are no errors in these files. they open in autocad without any problems, and my file checking utilities detect no errors.
when i attempt to do nothing other than open the file and write it back out, i get one of the following error messages:
- unexpected end of file
- invalid group code
both of these would end in a pure virtual method call, and occur on the line that writes the database out to file.
i haven't been able to detect any noticeable difference between files that work, and ones that don't. unfortunately, due to the data content of these files, i am unable to post them here. since i can't post the file, and don't know enough to reproduce the error in a new file, i don't expect that you'd be able to solve my problem, but i would be appreciate it if you could give me some sort of idea on where to look for the cause of this issue.
here's the open/write/close code i'm currently using:
// ... command line i/o handled before here ...
// create a custom services object.
odrxobjectimpl<myservices> svcs;
odinitialize(&svcs); // dwgdirect initialization
svcs.disableoutput(true); // don't print progress meter
oddbdatabaseptr pdb; // a smart pointer to a database
pdb = svcs.readfile(inputfilename, false, oda::ksharedenyno);
if(!pdb.isnull())
{
//code in here has been commented out for the moment
}
odrxobjectimpl<odwrfilebuf> fb;
fb.open(inputfilename);
pdb->writefile(&fb, filetype, outver);
//cleanup -- release database links
pdb.release(); //delete old database
oduninitialize(); //terminate dwggdirect
fb.close();
thanks in advance if anyone has any ideas.
little bit of a clarification
one point of clarification, these files work in the example code, and the one major difference between my code and the example code is that my code (as a requirement for my project) outputs to the same file that was read in.
quick fix for now...
quote:
originally posted by cbond
one point of clarification, these files work in the example code, and the one major difference between my code and the example code is that my code (as a requirement for my project) outputs to the same file that was read in.
since it seems that there is some sort of conflict between an open database, and writing back to the same file, i'm currently using a work-around that involves me writing to a new file, and then using system(); to move the output file back over the top of the input file.
this seems to add a bit of overhead with large files, so i would be interested in knowing if there was a way to make a database in memory write back to the file it is sourced from without this work-around.
thanks
check, please readfile() parameters.
it seems you use partial open mode with denyno. it results in reading and writing of the same file.
which dd version do you use? it seems the problem was fixed at least in 1.12.
sergey slezkin
yeah, ok. that does seem to make my work-around unnecessary, though it seems i had already commented out the part that had "denyno" in it (that must have happened after i wrote in my code fix).
i'm currently using 1.12.04
as a workaround you can:
1. not use partial open mode
or
2. if you need partial open mode and want to write to the same file call pdatabase->closeinput() before writefile().
sergey slezkin
ok, thanks
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