Re: [fpc-pascal] random "Disk Full" exceptions
Am Samstag, den 20.10.2007, 18:54 +0200 schrieb Jonas Maebe:
> On 20 Oct 2007, at 18:20, Marc Santhoff wrote:
>
> >> writeln(stderr, '--> hit found: '+inttostr(fcnt) + ' - ' +
> >> inttostr(PInteger(longint(adr)-longint(fx))^) + ' - ' +
> >> floattostr(PSingle(adr)^));
> >
> > Very nasty thing:
> >
> > The output channel is temporarily blocked and gives back "EAGAIN".
>
> I guess the initialisation code of the system unit should close and
> reopen stdin/out/err to make sure none of them is configured for non-
> blocking I/O.
Hm, I'm doing nothing but using an xterm for compiling and running the
program. System.pp does only open as far as I can tell:
...
procedure OpenStdIO(var f:text;mode,hdl:longint);
begin
Assign(f,'');
TextRec(f).Handle:=hdl;
TextRec(f).Mode:=mode;
TextRec(f).Closefunc:[EMAIL PROTECTED];
case mode of
fmInput :
TextRec(f).InOutFunc:[EMAIL PROTECTED];
fmOutput :
begin
TextRec(f).InOutFunc:[EMAIL PROTECTED];
if Do_Isdevice(hdl) then
TextRec(f).FlushFunc:[EMAIL PROTECTED];
end;
else
HandleError(102);
end;
end;
...
...
procedure SysInitStdIO;
begin
OpenStdIO(Input,fmInput,StdInputHandle);
OpenStdIO(Output,fmOutput,StdOutputHandle);
OpenStdIO(ErrOutput,fmOutput,StdErrorHandle);
OpenStdIO(StdOut,fmOutput,StdOutputHandle);
OpenStdIO(StdErr,fmOutput,StdErrorHandle);
end;
...
Begin
IsConsole := TRUE;
IsLibrary := FALSE;
StackLength := CheckInitialStkLen(InitialStkLen);
StackBottom := Sptr - StackLength;
{ Set up signals handlers }
InstallSignals;
{ Setup heap }
InitHeap;
SysInitExceptions;
{ Setup stdin, stdout and stderr }
SysInitStdIO;
{ Reset IO Error }
InOutRes:=0;
{ Arguments }
SetupCmdLine;
{ threading }
InitSystemThreads;
initvariantmanager;
initwidestringmanager;
End.
>
Maybe it is an OS fault(?) ...
Marc
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Re: [fpc-pascal] random "Disk Full" exceptions
On 20 Oct 2007, at 18:20, Marc Santhoff wrote: writeln(stderr, '--> hit found: '+inttostr(fcnt) + ' - ' + inttostr(PInteger(longint(adr)-longint(fx))^) + ' - ' + floattostr(PSingle(adr)^)); Very nasty thing: The output channel is temporarily blocked and gives back "EAGAIN". I guess the initialisation code of the system unit should close and reopen stdin/out/err to make sure none of them is configured for non- blocking I/O. Jonas ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] random "Disk Full" exceptions
Marc Santhoff wrote: >> writeln(stderr, '--> hit found: '+inttostr(fcnt) + ' - ' + >> inttostr(PInteger(longint(adr)-longint(fx))^) + ' - ' + >> floattostr(PSingle(adr)^)); > > Very nasty thing: > > The output channel is temporarily blocked and gives back "EAGAIN". This means the output channel is opened non-blocking. Is that intentional or a bug ? Micha ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] random "Disk Full" exceptions
Am Samstag, den 20.10.2007, 09:28 +0200 schrieb Marc Santhoff: > Hi, > > when running a program interacting with a c library accessing the disc > drive and writing some informational strings to "stderr" there are > thrown > >An unhandled exception occurred at $0804940D : >EInOutError : Disk Full > > exceptions randomly all over the place. The line position in the program > is constant but the amount of data processed is changing randomly. At > some runs no exception occurs at all. > > The source line is: > > writeln(stderr, '--> hit found: '+inttostr(fcnt) + ' - ' + > inttostr(PInteger(longint(adr)-longint(fx))^) + ' - ' + > floattostr(PSingle(adr)^)); Very nasty thing: The output channel is temporarily blocked and gives back "EAGAIN". This leads to exceptions thrown repeatedly which cannot be signaled because the output channel is blocked! I'm changing my practice of using stderr for debugging output, that much is sure. I know try ... except-blocks would come in handy, but I had to disable them for debugging purposes. Concluding I can say: fpc is too fast in writing for my computer! ;) Marc ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] random "Disk Full" exceptions
Am Samstag, den 20.10.2007, 11:05 +0200 schrieb Jonas Maebe: > On 20 Oct 2007, at 09:28, Marc Santhoff wrote: > > > > > Is there any debugging technique or some other information that can > > help > > me finding the cause? > > Run the program through strace to see what the actual error is. Some > unrelated error codes are also converted to "disk full" (such as > EFAULT). Haha! ... I myself tell people to use it and if the row is at me, I've forgotten. :D Thanks for reminding me, Marc ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] random "Disk Full" exceptions
On 20 Oct 2007, at 09:28, Marc Santhoff wrote: Is there any debugging technique or some other information that can help me finding the cause? Run the program through strace to see what the actual error is. Some unrelated error codes are also converted to "disk full" (such as EFAULT). Jonas ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
[fpc-pascal] random "Disk Full" exceptions
Hi, when running a program interacting with a c library accessing the disc drive and writing some informational strings to "stderr" there are thrown An unhandled exception occurred at $0804940D : EInOutError : Disk Full exceptions randomly all over the place. The line position in the program is constant but the amount of data processed is changing randomly. At some runs no exception occurs at all. The source line is: writeln(stderr, '--> hit found: '+inttostr(fcnt) + ' - ' + inttostr(PInteger(longint(adr)-longint(fx))^) + ' - ' + floattostr(PSingle(adr)^)); fx is an offset holding 33 and adr is a pointer into a block of memory alocated with getmem. The output is for debugging only. The error is happening when only read calls are made to the underlying file. If run in gdb the only message is: Program exited with code 0331. so no backtrace or the like. Is there any debugging technique or some other information that can help me finding the cause? If I use the heap trace unit (fpc -gh) the program fails at the first few lines, although apparently working correctly at that spot ... maybe a consequence of doing a lot pointer calculations. Helpless regards, Marc ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
