9 f__fatal (131, "I/O recursion");
10 if (a
->aunit
>= MXUNIT
|| a
->aunit
< 0)
11 err (a
->aerr
, 101, "rewind");
12 b
= &f__units
[a
->aunit
];
13 if (b
->ufd
== NULL
|| b
->uwrt
== 3)
16 err (a
->aerr
, 106, "rewind");
22 FSEEK (b
->ufd
, 0, SEEK_SET
);