54 lines
1.3 KiB
C
54 lines
1.3 KiB
C
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/*
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FUNCTION
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<<wcwidth>>---number of column positions of a wide-character code
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INDEX
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wcwidth
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ANSI_SYNOPSIS
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#include <wchar.h>
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int wcwidth(const wchar_t <[wc]>);
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TRAD_SYNOPSIS
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#include <wchar.h>
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int wcwidth(<[wc]>)
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wchar_t *<[wc]>;
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DESCRIPTION
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The <<wcwidth>> function shall determine the number of column
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positions required for the wide character wc. The application
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shall ensure that the value of wc is a character representable
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as a wchar_t, and is a wide-character code corresponding to a
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valid character in the current locale.
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RETURNS
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The <<wcwidth>> function shall either return 0 (if wc is a null
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wide-character code), or return the number of column positions to
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be occupied by the wide-character code wc, or return -1 (if wc
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does not correspond to a printable wide-character code).
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The current implementation of <<wcwidth>> simply sets the width
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of all printable characters to 1 since newlib has no character
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tables around.
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PORTABILITY
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<<wcwidth>> has been introduced in the Single UNIX Specification Volume 2
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<<wcwidth>> has been marked as extension in Single UNIX Specification Volume 3
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*/
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#include <_ansi.h>
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#include <wchar.h>
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#include <wctype.h>
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int
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_DEFUN (wcwidth, (wc),
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_CONST wchar_t wc)
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{
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if (iswprint (wc))
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return 1;
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if (iswcntrl (wc) || wc == L'\0')
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return 0;
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return -1;
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}
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