c++.dos.32-bits - Pointer Incrementation Problem - DAYSAGOF.C
Hi Walter, I have a problem with my pointer not incrementing
smoothly, one record to the next. (see code below)
While stepping through an array and watching in the data/object
window, the following is happening. (Imagine array numbered 1 to 10)
records
1,2,0,0,5,6,0,0,9,10....etc. So it misses some records yet catches
up, later. This is causing my pointer to go past the end of the array and
my program crash.
race_ctr = 0; /* find this race */
while( this_race_ptr->ref != this_run_ptr->ref
&& race_ctr < race_file_size )
{
race_ctr++;
this_race_ptr++;
}
The program compiles with no errors or warning messages. It's target is
Windows 95 and Console.
Maybe a clue here: When trying to locate the bug, after assigning
"this_race_ptr" to the "racemem_ptr" (allocated memory)
the following increment statements had no effect. this_race_ptr++;
(and the following) this_race_ptr += (race_file_size); Yet on other
pointers in the same location (after declaration, not in while loop)
they work as they should?
I have attached the source file.
Any help very much appreciated.
Paul
begin 0644 DAYSAGOF.C
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end
Nov 10 2003
"Walter" <walter digitalmars.com>
I'd start by loading the program up with printf's to trace its execution.
"Paul" <Paul_member pathlink.com> wrote in message
news:booboh$r0i$1 digitaldaemon.com...
Hi Walter, I have a problem with my pointer not incrementing
smoothly, one record to the next. (see code below)
While stepping through an array and watching in the data/object
window, the following is happening. (Imagine array numbered 1 to 10)
records
1,2,0,0,5,6,0,0,9,10....etc. So it misses some records yet catches
up, later. This is causing my pointer to go past the end of the array and
my program crash.
race_ctr = 0; /* find this race */
while( this_race_ptr->ref != this_run_ptr->ref
&& race_ctr < race_file_size )
{
race_ctr++;
this_race_ptr++;
}
The program compiles with no errors or warning messages. It's target is
Windows 95 and Console.
Maybe a clue here: When trying to locate the bug, after assigning
"this_race_ptr" to the "racemem_ptr" (allocated memory)
the following increment statements had no effect. this_race_ptr++;
(and the following) this_race_ptr += (race_file_size); Yet on other
pointers in the same location (after declaration, not in while loop)
they work as they should?
I have attached the source file.
Any help very much appreciated.
Paul
Nov 10 2003