The Open Group Base Specifications Issue 7, 2018 edition
IEEE Std 1003.1-2017 (Revision of IEEE Std 1003.1-2008)
Copyright © 2001-2018 IEEE and The Open Group
ffs - find first set bit
The ffs() function shall find the first bit set (beginning with the least significant bit) in i, and return the
index of that bit. Bits are numbered starting at one (the least significant bit).
The ffs() function shall return the index of the first bit set. If i is 0, then ffs() shall return 0.
No errors are defined.
The following sections are informative.
First released in Issue 4, Version 2.
Moved from X/OPEN UNIX extension to BASE.
End of informative text.
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