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 GroupA newer edition of this document exists here
NAME
ffs - find first set bit
SYNOPSIS
DESCRIPTION
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).
RETURN VALUE
The ffs() function shall return the index of the first bit set. If i is 0, then ffs() shall return 0.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
XBD <strings.h>
CHANGE HISTORY
First released in Issue 4, Version 2.
Issue 5
Moved from X/OPEN UNIX extension to BASE.
End of informative text.
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