rand() always returns 18467...whats going on.. [modified]

[montiee]

For the life of me I can't work this out. In the "apps" InitInstance I seed the random number generator by calling srand(time(NULL)); Then in a thread whenever I invoke rand() and print it out via cout it always has the value of 18467. Now rand() is invoked every minute or two so it's not like it's in a tight loop or anything like that. I never call srand again either. Just the once in the apps InitInstance function. Anyone experienced this problem before? Currently using Visual Studio 2008. I even went so far as to apply SP1 to it just incase something was fixed. Such a simple thing not working is really annoying me. Just to add if I print out rand() a few times in the apps InitInstance it works as expected. However once I call it from a UI thread it's always the same number.

modified on Monday, September 1, 2008 3:30 PM

[Mark Salsbery]

jbem wrote:

In the "apps" InitInstance I seed the random number generator by calling srand(time(NULL));

jbem wrote:

Then in a thread whenever I invoke rand()

srand() is thread specific. You need to seed (call srand()) on every thread that will call rand(). Mark

Mark Salsbery Microsoft MVP - Visual C++ :java:

[montiee]

Thanks. That did the trick.