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32 * @(#)wsetup.c 8.1 (Berkeley) 6/4/93
33 * $FreeBSD: src/lib/libc/stdio/wsetup.c,v 1.11 2009/01/08 06:38:06 das Exp $
42 * Various output routines call wsetup to be sure it is safe to write,
43 * because either _flags does not include __SWR, or _buf is NULL.
44 * _wsetup returns 0 if OK to write; otherwise, it returns EOF and sets errno.
49 /* make sure stdio is set up */
54 * If we are not writing, we had better be reading and writing.
56 if ((fp->pub._flags & __SWR) == 0) {
57 if ((fp->pub._flags & __SRW) == 0) {
59 fp->pub._flags |= __SERR;
62 if (fp->pub._flags & __SRD) {
63 /* clobber any ungetc data */
66 fp->pub._flags &= ~(__SRD|__SEOF);
68 fp->pub._p = fp->_bf._base;
70 fp->pub._flags |= __SWR;
74 * Make a buffer if necessary, then set _w.
76 if (fp->_bf._base == NULL)
78 if (fp->pub._flags & __SLBF) {
80 * It is line buffered, so make _lbfsize be -_bufsize
81 * for the putc() macro. We will change _lbfsize back
82 * to 0 whenever we turn off __SWR.
85 fp->pub._lbfsize = -fp->_bf._size;
87 fp->pub._w = fp->pub._flags & __SNBF ? 0 : fp->_bf._size;