extern int os_open_file(char *file, struct openflags flags, int mode);
extern int os_read_file(int fd, void *buf, int len);
extern int os_write_file(int fd, const void *buf, int count);
-extern int os_file_size(char *file, long long *size_out);
+extern int os_file_size(char *file, unsigned long long *size_out);
extern int os_file_modtime(char *file, unsigned long *modtime);
extern int os_pipe(int *fd, int stream, int close_on_exec);
extern int os_set_fd_async(int fd, int owner);
extern void os_kill_ptraced_process(int pid, int reap_child);
extern void os_usr1_process(int pid);
extern int os_getpid(void);
+extern int os_getpgrp(void);
extern int os_map_memory(void *virt, int fd, unsigned long long off,
unsigned long len, int r, int w, int x);