forked from KolibriOS/kolibrios
46 lines
964 B
C
46 lines
964 B
C
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/*
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FUNCTION
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<<isxdigit>>---hexadecimal digit predicate
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INDEX
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isxdigit
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ANSI_SYNOPSIS
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#include <ctype.h>
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int isxdigit(int <[c]>);
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TRAD_SYNOPSIS
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#include <ctype.h>
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int isxdigit(int <[c]>);
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DESCRIPTION
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<<isxdigit>> is a macro which classifies ASCII integer values by table
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lookup. It is a predicate returning non-zero for hexadecimal digits,
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and <<0>> for other characters. It is defined only if <[c]> is
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representable as an unsigned char or if <[c]> is EOF.
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You can use a compiled subroutine instead of the macro definition by
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undefining the macro using `<<#undef isxdigit>>'.
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RETURNS
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<<isxdigit>> returns non-zero if <[c]> is a hexadecimal digit
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(<<0>>--<<9>>, <<a>>--<<f>>, or <<A>>--<<F>>).
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PORTABILITY
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<<isxdigit>> is ANSI C.
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No supporting OS subroutines are required.
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*/
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#include <_ansi.h>
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#include <ctype.h>
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#undef isxdigit
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int
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_DEFUN(isxdigit,(c),int c)
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{
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return(__ctype_ptr__[c+1] & ((_X)|(_N)));
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}
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