Problem with elapsed time functions

[Ing. Antonio Quesada Duarte]

Hi there!
I'm developing a project for one of my classes, and it involves benchmarks. 
Therefore, i need to use functions like:
idate
itime
etime
fdate
   
   but when i try to link the program the linker says it can't find those
functions.
   Does anybody in netland know in which library can i find them?
   Thanks a lot!!

>From Monterrey, Mexico:
Antonio Quesada Duarte
aquesada at academ01.mty.itesm.mx