Only get non-static functions in ctags.

command.bash

$ gcc -E main.c | ./filter.py > temp.c && ctags --c-types=f -x --file-scope=no temp.c
main             function     25 temp.c           int main(void) {
test             function     17 temp.c           int test() {

filter.py

#!/usr/bin/env python3
import sys

skip = False
for l in sys.stdin:
    if not skip:
        sys.stdout.write(l)
    if l.startswith("# "):
        toks = l.strip().split(" ")
        linenum, filename = toks[1:3]
        flags = toks[3:]
        skip = "3" in flags

        

main.c

#include <stdio.h>

#define my_test static

static void static_test() {
  
}

int test() {
    printf("%d", 6);
}

my_test void foo2() {
    printf("%d", 5);
}

int main(void) {
    foo2();
    return 0;
}