30 lines
414 B
C
30 lines
414 B
C
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/* ffs -- Find the first bit set in the parameter
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NAME
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ffs -- Find the first bit set in the parameter
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SYNOPSIS
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int ffs (int valu)
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DESCRIPTION
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Find the first bit set in the parameter. Bits are numbered from
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right to left, starting with bit 1.
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*/
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int
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ffs (valu)
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register int valu;
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{
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register int bit;
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if (valu == 0)
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return 0;
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for (bit = 1; !(valu & 1); bit++)
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valu >>= 1;
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return bit;
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}
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