Re: Access violation at the end of the program
On Aug 28, 5:04 pm, "Larry Smith" <no_spam@_nospam.com> wrote:
I got this str-r-r-range problem, at the end of my program I get an
access violation. Not, while the AV itself isn't a strange thig,
what's strange is WHEN i get it. It get it after the last RETURN is
executed. I mean, the program runs, and does exactly what it's
supposed to, but crushes at the very end of it. Using the debugger, I
found that after the cpoletion of it's last line, which is the exiting
"return" the execution jumps to some strange locatin, where all the
memory slots are full of ??, and that's when the exception pop-up
jumps.
The pop-up says: "The instruction at "0x00007478" referenced memory at
"0x00007478". The memory could not be "read".
Does anyone have any idea about "why" that could happen and how can I
fix it?
Also, if it would help, I could just post here the whole program, it's
not big, about 2 pages of text.
Thanks.
Oh, and if has any importance:
I got PC running WIn2000, and a VC++ 6.0.
Do you have any destructors? If so then comment them all out and see if
the
problem persists. If the problem disappears then uncomment them one by
one
until the problem disappears. As soon as it does then you've (likely)
found
your problem (a destructor is freeing some resource that's already been
freed typically).
Anyway, I //ed the only fclose I have. No luck, still got Acc. Voilat.
You shouldn't close it twice. Since you've commented it out however out and
the problem persists then you may simply be corrupting something elsewhere
(but it's not manifesting itself until shutdown). Show your code which
hopefully doesn't exceed the 2 pages you mentioned. I'll take a quick look
but can't promise anything since my time is limited.
Sure, thank you very much, here it is (please don't LOL me):
#include <time.h>
#include <stdio.h>
#include <conio.h>
#include <windows.h>
#define EXT "txt"
#define ESC_CODE 27
#define SPACE_CODE 32
// Func Prots
void SetFileName( char *filename);
void RetrieveDateTime(char *SystemTimeChar);
void LogEvent2File( FILE *file, int event_counter);
// Global Vars
char SystemTimeChar[] = "yyyy_mm_dd-HH_mm_ss_ccc";
void main ()
{
char logfilename[] = "EV_yymmdd_hhmmssccc.txt";
int evnt_cntr=0;
char keyval=0;
FILE *outfile=NULL;
SetFileName (logfilename);
if(!(outfile = fopen(logfilename,"w")))
{
printf("Cannot open output file. Program will end now.");
getch();
return;
}
printf("** Started output file: %s**\n", logfilename);
printf("** Press SPACEBAR for event, ESCAPE for exit **\n");
printf("Time(DD/MM/YY-HH:MM:SS.ms)\tEvent Number\n");
while (1)
{
if( kbhit())
{
keyval=getch();
if(keyval == ESC_CODE)
break;
else if(keyval == SPACE_CODE)
LogEvent2File(outfile, ++evnt_cntr);
}
}
if(fclose(outfile))
{
printf("Cannot close output file. Program will end now.");
getch();
return;
}
printf("** Stopped output file: %s**\n", logfilename);
return;
}
/////////// Func Defs //////////////
void RetrieveDateTime(char *SystemTimeChar)
{ // return date and time format: yyyy_mm_dd-HH_mm_ss_ccc
SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
sprintf(SystemTimeChar, "%04d_%02d_%02d-%02d_%02d_%02d_%03d",
SysTime.wYear, SysTime.wMonth,\
SysTime.wDay, SysTime.wHour, SysTime.wMinute, SysTime.wSecond,
SysTime.wMilliseconds);
return;
} // RetrieveDateTime
void SetFileName(char *filename)
{
RetrieveDateTime(SystemTimeChar);
sprintf(filename, "EV-%s.%s", SystemTimeChar, EXT);
return;
} // SetFileName
void LogEvent2File( FILE *file, int event_counter)
{
RetrieveDateTime(SystemTimeChar);
fprintf(file, "%c%c%c%c/%c%c/%c%c-%c%c:%c%c:%c%c.%c%c%c\t%d\n",
SystemTimeChar[0],\
SystemTimeChar[1], SystemTimeChar[2], SystemTimeChar[3],
SystemTimeChar[5],\
SystemTimeChar[6], SystemTimeChar[8], SystemTimeChar[9],
SystemTimeChar[11],\
SystemTimeChar[12], SystemTimeChar[14], SystemTimeChar[15],
SystemTimeChar[17],\
SystemTimeChar[18], SystemTimeChar[20], SystemTimeChar[21],
SystemTimeChar[22],\
event_counter);
printf(" %c%c%c%c/%c%c/%c%c-%c%c:%c%c:%c%c.%c%c%c\t%d\n",
SystemTimeChar[0],\
SystemTimeChar[1], SystemTimeChar[2], SystemTimeChar[3],
SystemTimeChar[5],\
SystemTimeChar[6], SystemTimeChar[8], SystemTimeChar[9],
SystemTimeChar[11],\
SystemTimeChar[12], SystemTimeChar[14], SystemTimeChar[15],
SystemTimeChar[17],\
SystemTimeChar[18], SystemTimeChar[20], SystemTimeChar[21],
SystemTimeChar[22],\
event_counter);
return;
} // LogEvent2File