| 1 | FFS(3) BSD Programmer's Manual FFS(3) |
| 2 | |
| 3 | N\bNA\bAM\bME\bE |
| 4 | f\bff\bfs\bs - find first bit set in a bit string |
| 5 | |
| 6 | S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS |
| 7 | #\b#i\bin\bnc\bcl\blu\bud\bde\be <\b<s\bst\btr\bri\bin\bng\bg.\b.h\bh>\b> |
| 8 | |
| 9 | _\bi_\bn_\bt |
| 10 | f\bff\bfs\bs(_\bi_\bn_\bt _\bv_\ba_\bl_\bu_\be); |
| 11 | |
| 12 | D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN |
| 13 | The f\bff\bfs\bs() fucntion finds the first bit set in _\bv_\ba_\bl_\bu_\be and returns the index |
| 14 | of that bit. Bits are numbered starting from 1, starting at the right- |
| 15 | most bit. A return value of 0 means that the argument was zero. |
| 16 | |
| 17 | S\bSE\bEE\bE A\bAL\bLS\bSO\bO |
| 18 | bitstring(3) |
| 19 | |
| 20 | H\bHI\bIS\bST\bTO\bOR\bRY\bY |
| 21 | The f\bff\bfs\bs() function appeared in 4.3BSD. |
| 22 | |
| 23 | 4.4BSD June 4, 1993 1 |