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);
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);