[Gambas-user] Very strange printing problem + SHELL

[Eilert]

Benoit Minisini schrieb:
> On Wednesday 03 May 2006 09:52, Eilert wrote:
>> Hi everybody,
>>
>> After having been searching for this bug for months, I've found it at last.
>>
>> In one of my apps, when the user makes an entry into a customer's
>> account for instance and has it saved, the program won't print anymore.
>> The printing dialog appears, and everything runs through as expected,
>> but there is no output to the printer. If I restart the program, it will
>> print as usual.
>>
>> Now, this appears to be the reason:
>>
>> In the saving SUB I found I had included a SHELL command changing the
>> file's mode to 660 after writing so every member of the group can write
>> into this file.
>>
>> When I comment this SHELL command out, the app runs as expected. As soon
>> as it is activated, however, the bug appears: Whenever the SHELL is
>> called, printing will fail afterwards.
>>
>> Here is one of the critical parts in code:
>>
>>    OPEN datei$ & "konto" FOR WRITE CREATE AS #dtnr
>>      FOR i = 0 TO ktNr.Count - 1
>>        IF ktModus[i] = "N" THEN BREAK
>>        PRINT #dtnr, "    account" & Chr$(13)
>>        PRINT #dtnr, "        number=" & CStr(i + 1) & Chr$(13)
>>        PRINT #dtnr, "        date=" & SpeicherDatum(ktDatum[i]) & Chr$(13)
>>        PRINT #dtnr, "        text=" & Str2Tag(ktText[i]) & Chr$(13)
>>        PRINT #dtnr, "        debit=" & ktSoll[i] & Chr$(13)
>>        PRINT #dtnr, "        credit=" & ktHaben[i] & Chr$(13)
>>        PRINT #dtnr, "        mode=" & SpeicherModus(ktModus[i]) & Chr$(13)
>>        PRINT #dtnr, "    end account" & Chr$(13)
>>        PRINT #dtnr, " " & Chr$(13)
>>      NEXT
>>    CLOSE #dtnr
>>    SHELL "chmod 660 " & datei$ & "konto" WAIT
>>
>> Does anyone here have an idea why this SHELL line might keep the printer
>> from printing? Is there another way of having the chmod 660? Or did I
>> implement the SHELL command wrong?
>>
>> Thanks for all ideas!
>>
>> Rolf
>>
> 
> I think there is a clash between interpreter process management and qt process 
> management, used for running 'lpr'.
> 
> Try to print to a postscript file, and send this file to the printer with 
> SHELL or EXEC. It should work.
> 
> Regards,
> 

Yes. In my app, there is a printer dialog. If I choose "print to file", 
it prints a standard ps file.

Hm. Is deviating the printing through a ps file + SHELL to lpr really 
the only way of getting rid of this problem?

Rolf