50 lines
873 B
C
50 lines
873 B
C
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/*
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FUNCTION
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<<strnlen>>---character string length
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INDEX
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strnlen
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ANSI_SYNOPSIS
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#include <string.h>
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size_t strnlen(const char *<[str]>, size_t <[n]>);
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TRAD_SYNOPSIS
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#include <string.h>
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size_t strnlen(<[str]>, <[n]>)
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char *<[src]>;
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size_t <[n]>;
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DESCRIPTION
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The <<strnlen>> function works out the length of the string
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starting at <<*<[str]>>> by counting chararacters until it
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reaches a NUL character or the maximum: <[n]> number of
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characters have been inspected.
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RETURNS
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<<strnlen>> returns the character count or <[n]>.
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PORTABILITY
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<<strnlen>> is a Gnu extension.
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<<strnlen>> requires no supporting OS subroutines.
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*/
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#undef __STRICT_ANSI__
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#include <_ansi.h>
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#include <string.h>
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size_t
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_DEFUN (strnlen, (str, n),
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_CONST char *str _AND
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size_t n)
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{
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_CONST char *start = str;
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while (*str && n-- > 0)
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str++;
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return str - start;
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}
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