- IV (*Fileno)(PerlIO *f);
- PerlIO * (*Fdopen)(PerlIO_funcs *tab, int fd, const char *mode);
- PerlIO * (*Open)(PerlIO_funcs *tab, const char *path, const char *mode);
- int (*Reopen)(const char *path, const char *mode, PerlIO *f);
- IV (*Pushed)(PerlIO *f,const char *mode,const char *arg,STRLEN len);