difference between #if defined(WIN32) and #ifdef(WIN32)

Question

I am compiling my program that will running on linux gcc 4.4.1 C99.

I was just putting my #defines in to separate the code that will be compiled on either windows o

Answer 1

#ifdef FOO

and

#if defined(FOO)

are the same,

but to do several things at once, you can use defined, like

#if defined(FOO) || defined(BAR)