From PellesC help or commandline:
/E Runs the preprocessor only (to stdout).
>pocc.exe
Pelles ISO C Compiler, Version 6.00.6
Copyright (c) Pelle Orinius 1999-2009
Syntax:
POCC [options] srcfile{.c|.asm}
Options:
/D<name>[=<text>] Define a preprocessor symbol
/E Preprocess only (to stdout)
/Fo<outfile> Name the output file
...