Re: integer in ostringstream
On May 26, 10:43 am, Bart van Ingen Schenau <b...@ingen.ddns.info>
wrote:
cerr wrote:
Hi Chris,
Thanks for your reply!
getPriorityNeed() looks is just a simple method to read an integer in
a thread safe manner:
int GPSData::getPriorityNeed()
{
int value;
novax_thread_lock(&priorityNeed_mtx);
//calculate priority with data from config file and deviation
from
INIT!
value = GPSData::priorityNeed;
novax_thread_unlock(&priorityNeed_mtx);
return value;
}
GPSData::priorityNeed gets set by
void GPSData::setPriorityNeed(int value)
{
novax_thread_lock(&priorityNeed_mtx);
GPSData::priorityNeed = value;
novax_thread_unlock(&priorityNeed_mtx);
}
which gets called regularly from a thread.
The object GPSData::priorityNeed is declared as a private integer.
So why would getPriorityNeed return a correct value most of the times
but every now and then it seems to mess it up... Not very often tho
and as said, I can't really figure out any regularity... :o
There are two possible causes for that wrong value to turn up:
1. An incorrect value gets passed to setPriorityNeed. This should be
caught with an assert in setPriorityNeed, after which you can trace back
in the debugger who is responsible for that wrong value.
Thats' what I thought as well first but then again, the value that
gets set there is from the type bool (in this case, can be integer in
other cases that's why i'm using int as the type to save the value)
2. You have a rogue pointer in your program that causes the value of
GPSData::priorityNeed to be overwritten. This is a very serious problem
that can only be located with a lot of hard effort and critically
looking at ALL of the code.
Nu-uh, I don't think so as the other values from the same pointer are
always correct. I believe it is as fenghuang earlier suggested "just"
a casting issue:
char * str = NULL;
char ch = '\0';
int i = 0;
// in fact, the three variables have same content
but
std::cout << str;
std::cout << ch;
std::cout << 0;
have different results
Thanks,
--
roN
--
[ See http://www.gotw.ca/resources/clcm.htm for info about ]
[ comp.lang.c++.moderated. First time posters: Do this! ]