GCC -E preprocessor output

Question

I am trying to preprocess ah file and produce a new.h file with all of the # preproc directives resolved. I used gcc -E file.c command and I always get this output:

# 1 "file.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "file.c"

Which command should I use to produce a new preprocessed.h file?

Answer 1

From https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html

-P
Inhibit generation of linemarkers in the output from the preprocessor. This might be useful when running the preprocessor on something that is not C code, and will be sent to a program which might be confused by the linemarkers.

Simply use

gcc -E -P file.c