implicit declaration of function usleep

Question

gcc (GCC) 4.6.3
c89

I am trying to use usleep. However, I keep getting the following warning:

implicit declarat

Answer 1

This may work: Add -std=gnu99 when compiling with gcc on Linux.

Example:

arm-linux-gcc -lpthread -std=gnu99  -o test ArmLinuxDataPipe1.2.1.c