forked from KolibriOS/kolibrios
49 lines
966 B
C
49 lines
966 B
C
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/*
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FUNCTION
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<<iscntrl>>---control character predicate
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INDEX
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iscntrl
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ANSI_SYNOPSIS
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#include <ctype.h>
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int iscntrl(int <[c]>);
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TRAD_SYNOPSIS
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#include <ctype.h>
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int iscntrl(<[c]>);
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DESCRIPTION
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<<iscntrl>> is a macro which classifies ASCII integer values by table
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lookup. It is a predicate returning non-zero for control characters, and 0
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for other characters. It is defined only if <[c]> is representable as an
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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 iscntrl>>'.
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RETURNS
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<<iscntrl>> returns non-zero if <[c]> is a delete character or ordinary
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control character (<<0x7F>> or <<0x00>>--<<0x1F>>).
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PORTABILITY
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<<iscntrl>> 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 iscntrl
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int
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_DEFUN(iscntrl,(c),int c)
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{
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return(__ctype_ptr__[c+1] & _C);
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}
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