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/*
FUNCTION
<<ffs>>---find first bit set in a word
INDEX
ffs
ANSI_SYNOPSIS
int ffs(int <[word]>);
TRAD_SYNOPSIS
int ffs(<[word]>);
DESCRIPTION
<<ffs>> returns the first bit set in a word.
RETURNS
<<ffs>> returns 0 if <[c]> is 0, 1 if <[c]> is odd, 2 if <[c]> is a multiple of
2, etc.
PORTABILITY
<<ffs>> is not ANSI C.
No supporting OS subroutines are required. */
#include <strings.h>
int
_DEFUN(ffs, (word),
int word)
{
int i;
if (!word)
return 0;
i = 0;
for (;;)
{
if (((1 << i++) & word) != 0)
return i;
}
}
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