FLS(9) Basic C Library Functions FLS(9)

NAME fls - find last set bit in word

SYNOPSIS int fls(int x);

ARGUMENTS x the word to search

DESCRIPTION This is defined in a similar way as the libc and compiler builtin ffs, but returns the position of the most significant set bit.

fls(value) returns 0 if value is 0 or the position of the last set bit if value is nonzero. The last (most significant) bit is at position 32.

COPYRIGHT Kernel Hackers Manual 2.6. January 2013 FLS(9)