[444] | 1 | /* |
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| 2 | FUNCTION |
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| 3 | <<fwide>>---set and determine the orientation of a FILE stream |
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| 4 | |
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| 5 | INDEX |
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| 6 | fwide |
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| 7 | INDEX |
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| 8 | _fwide_r |
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| 9 | |
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| 10 | SYNOPSIS |
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| 11 | #include <wchar.h> |
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| 12 | int fwide(FILE *<[fp]>, int <[mode]>); |
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| 13 | |
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| 14 | int _fwide_r(struct _reent *<[ptr]>, FILE *<[fp]>, int <[mode]>); |
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| 15 | |
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| 16 | DESCRIPTION |
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| 17 | When <[mode]> is zero, the <<fwide>> function determines the current |
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| 18 | orientation of <[fp]>. It returns a value > 0 if <[fp]> is |
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| 19 | wide-character oriented, i.e. if wide character I/O is permitted but |
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| 20 | char I/O is disallowed. It returns a value < 0 if <[fp]> is byte |
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| 21 | oriented, i.e. if char I/O is permitted but wide character I/O is |
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| 22 | disallowed. It returns zero if <[fp]> has no orientation yet; in |
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| 23 | this case the next I/O operation might change the orientation (to byte |
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| 24 | oriented if it is a char I/O operation, or to wide-character oriented |
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| 25 | if it is a wide character I/O operation). |
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| 26 | |
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| 27 | Once a stream has an orientation, it cannot be changed and persists |
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| 28 | until the stream is closed, unless the stream is re-opened with freopen, |
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| 29 | which removes the orientation of the stream. |
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| 30 | |
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| 31 | When <[mode]> is non-zero, the <<fwide>> function first attempts to set |
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| 32 | <[fp]>'s orientation (to wide-character oriented if <[mode]> > 0, or to |
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| 33 | byte oriented if <[mode]> < 0). It then returns a value denoting the |
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| 34 | current orientation, as above. |
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| 35 | |
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| 36 | RETURNS |
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| 37 | The <<fwide>> function returns <[fp]>'s orientation, after possibly |
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| 38 | changing it. A return value > 0 means wide-character oriented. A return |
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| 39 | value < 0 means byte oriented. A return value of zero means undecided. |
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| 40 | |
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| 41 | PORTABILITY |
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| 42 | C99, POSIX.1-2001. |
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| 43 | |
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| 44 | */ |
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| 45 | |
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| 46 | #include <_ansi.h> |
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| 47 | #include <wchar.h> |
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| 48 | #include "local.h" |
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| 49 | |
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| 50 | int |
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| 51 | _fwide_r (struct _reent *ptr, |
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| 52 | FILE *fp, |
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| 53 | int mode) |
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| 54 | { |
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| 55 | int ret; |
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| 56 | |
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| 57 | CHECK_INIT(ptr, fp); |
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| 58 | |
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| 59 | _newlib_flockfile_start (fp); |
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| 60 | if (mode != 0) { |
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| 61 | ORIENT (fp, mode); |
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| 62 | } |
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| 63 | if (!(fp->_flags & __SORD)) |
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| 64 | ret = 0; |
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| 65 | else |
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| 66 | ret = (fp->_flags2 & __SWID) ? 1 : -1; |
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| 67 | _newlib_flockfile_end (fp); |
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| 68 | return ret; |
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| 69 | } |
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| 70 | |
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| 71 | int |
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| 72 | fwide (FILE *fp, |
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| 73 | int mode) |
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| 74 | { |
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| 75 | return _fwide_r (_REENT, fp, mode); |
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| 76 | } |
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