| re: Problem with time() using g++
Mike Alexeev wrote:[color=blue]
> Hi all,
> I have come across very strange behavior of the return value of the
> time() function. Below is the program to illustrate the problem: The
> value of NOW somehow changes after the call to the ifstream
> constructor.
>
> #include <iostream>
> #include <fstream>
> #include <time.h>
>
> int main(int argc, char** argv)
> {
> if (argc != 2)
> {
> std::cout << "Usage: ctest filename" << std::endl;
> exit(-1);
> }
> time_t NOW = time(0);
> std::cout << "Start time before the call to ifstream(): NOW="
> << NOW << std::endl;
> std::ifstream infile(argv[1]);
> std::cout << "Start time after the call to ifstream(): NOW="
> << NOW << std::endl;
> infile.close();
> exit(0);
> }
>
> I tried this program with g++ 3.1.1 compiler on Solaris 5.8 and here
> is the output:
>
>[color=green]
>>g++ -o test test.cxx
>>test test.cxx[/color]
>
> Time before the call to ifstream(): NOW=1083075439
> Time after the call to ifstream(): NOW=27503
>
>
> Given the signature of the time() (time_t time(time_t* t)) I was not
> able to find any reasonable explanation how the call to the ifstream
> constructor could affect the local variable it does not know about so
> any help would be greatly appreciated.
>
> By the way, I tried the same program with CC Sun Workshop 6.2 and it
> works fine.
>[color=green]
>>CC -o test test.cxx
>> test test.cxx[/color]
>
> Time before the call to ifstream(): NOW=1083075848
> Time after the call to ifstream(): NOW=1083075848[/color]
Try putting this after your #include's:
#undef NOW
Alternatively, don't use all-caps identifiers for anything but macros.
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