1 #include "stdio_impl.h"
3 /* The behavior of this function is undefined except when it is the first
4 * operation on the stream, so the presence or absence of locking is not
5 * observable in a program whose behavior is defined. Thus no locking is
6 * performed here. No allocation of buffers is performed, but a buffer
7 * provided by the caller is used as long as it is suitably sized. */
9 int setvbuf(FILE *restrict f, char *restrict buf, int type, size_t size)
16 if (buf && size >= UNGET) {
18 f->buf_size = size - UNGET;
20 if (type == _IOLBF && f->buf_size)