Section (3) ffs
ffs, ffsl, ffsll — find first bit set in a word
||long int i
||long long int i
ffs() function returns
the position of the first (least significant) bit set in the
i. The least
significant bit is position 1 and the most significant
position is, for example, 32 or 64. The functions
ffsl() do the same but take arguments of
possibly different size.
These functions return the position of the first bit set,
or 0 if no bits are set in
For an explanation of the terms used in this section, see attributes(7).
ffsll() functions are glibc extensions.
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Copyright 1993 David Metcalfe (davidprism.demon.co.uk)
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Linux libc source code
Lewine_zsingle_quotesz_s _POSIX Programmer_zsingle_quotesz_s Guide_ (O_zsingle_quotesz_Reilly & Associates, 1991)
386BSD man pages
Modified Sat Jul 24 19:39:35 1993 by Rik Faith (faithcs.unc.edu)
Modified 2003 Walter Harms (walter.harmsinformatik.uni-oldenburg.de)