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#include <strings.h> int ffs(int i); int ffsl(long i); int ffsll(long long i); int fls(int i); int flsl(long i); int flsll(long long i);
The ffs(), ffsl(), and ffsll() functions finds the first bit set (beginning with the least significant bit) and return the index of that bit. Bits are numbered starting at one (the least significant bit).
The fls(), flsl(), and flsll() functions find the last bit set (beginning with the least significant bit) and return the index of that bit. Bits are numbered starting at one (the least significant bit).
The ffs(), ffsl(), and ffsll() functions returns the index of the first bit set. If i is 0, then they return 0.
The fls(), flsl(), and flsll() functions return the index of the last bit set. If i is 0, then they return 0.
No errors are defined.
See attributes(7) for descriptions of the following attributes:
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Committed |
| MT-Level MT-Safe |
attributes (7), standards (7)