Function cleanup_path_exists

tests/repro/repro_harness_cleanup.c:8–11

#include <sys/stat.h>

static int cleanup_path_exists(const char *path) {
    struct stat st;
    return path && path[0] && stat(path, &st) == 0;
}

static int cleanup_write_sentinel(const char *path) {
    FILE *file = cbm_fopen(path, "wb");