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author | des <des@FreeBSD.org> | 2004-01-13 16:05:47 +0000 |
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committer | des <des@FreeBSD.org> | 2004-01-13 16:05:47 +0000 |
commit | ec1fd605cbbcb4bc5ec851a6775a363b01d56029 (patch) | |
tree | ec554f27ccb99efb17cf19602b6279f86f0db08b /lib/libc/string/ffs.3 | |
parent | dfa545653779c51e8c959ed4a6ebb441f043566c (diff) | |
download | FreeBSD-src-ec1fd605cbbcb4bc5ec851a6775a363b01d56029.zip FreeBSD-src-ec1fd605cbbcb4bc5ec851a6775a363b01d56029.tar.gz |
Add and document ffsl(), fls() and flsl().
Diffstat (limited to 'lib/libc/string/ffs.3')
-rw-r--r-- | lib/libc/string/ffs.3 | 41 |
1 files changed, 35 insertions, 6 deletions
diff --git a/lib/libc/string/ffs.3 b/lib/libc/string/ffs.3 index 5b5fb6f..cb9c6cc 100644 --- a/lib/libc/string/ffs.3 +++ b/lib/libc/string/ffs.3 @@ -38,23 +38,44 @@ .Dt FFS 3 .Os .Sh NAME -.Nm ffs -.Nd find first bit set in a bit string +.Nm ffs , +.Nm ffsl , +.Nm fls , +.Nm flsl +.Nd find first or last bit set in a bit string .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In strings.h .Ft int .Fn ffs "int value" +.Ft int +.Fn ffsl "long value" +.Ft int +.Fn fls "int value" +.Ft int +.Fn flsl "long value" .Sh DESCRIPTION The .Fn ffs -function finds the first bit set in +and +.Fn ffsl +functions find the first bit set in .Fa value -and returns the index of that bit. +and return the index of that bit. +.Pp +The +.Fn fls +and +.Fn flsl +functions find the last bit set in +.Fa value +and return the index of that bit. +.Pp Bits are numbered starting from 1, starting at the right-most -bit. -A return value of 0 means that the argument was zero. +(least significant) bit. +A return value of zero from any of these functions means that the +argument was zero. .Sh SEE ALSO .Xr bitstring 3 .Sh HISTORY @@ -69,3 +90,11 @@ before it was moved to for .St -p1003.1-2001 compliance. +.Pp +The +.Fn ffsl , +.Fn fls +and +.Fn flsl +functions appeared in +.Fx 5.3 . |