0,0 → 1,46 |
/* |
FUNCTION |
<<isalnum>>---alphanumeric character predicate |
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INDEX |
isalnum |
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ANSI_SYNOPSIS |
#include <ctype.h> |
int isalnum(int <[c]>); |
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TRAD_SYNOPSIS |
#include <ctype.h> |
int isalnum(<[c]>); |
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DESCRIPTION |
<<isalnum>> is a macro which classifies ASCII integer values by table |
lookup. It is a predicate returning non-zero for alphabetic or |
numeric ASCII characters, and <<0>> for other arguments. It is defined |
for all integer values. |
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You can use a compiled subroutine instead of the macro definition by |
undefining the macro using `<<#undef isalnum>>'. |
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RETURNS |
<<isalnum>> returns non-zero if <[c]> is a letter (<<a>>--<<z>> or |
<<A>>--<<Z>>) or a digit (<<0>>--<<9>>). |
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PORTABILITY |
<<isalnum>> is ANSI C. |
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No OS subroutines are required. |
*/ |
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#include <_ansi.h> |
#include <ctype.h> |
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#undef isalnum |
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int |
_DEFUN(isalnum,(c),int c) |
{ |
return(__ctype_ptr__[c+1] & (_U|_L|_N)); |
} |
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