.\" Id: bitncmp.mdoc,v 1.3 2004/03/09 06:30:07 marka Exp 
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.Dd June 1, 1996
.Dt BITNCMP 3
.Os BSD 4
.Sh NAME
.Nm bitncmp 
.Nd compare bit masks
.Sh SYNOPSIS
.Ft int
.Fn bitncmp "const void *l" "const void *r" "int n"
.Sh DESCRIPTION
The function
.Fn bitncmp
compares the
.Dq Fa n
most-significant bits of the two masks pointed to by
.Dq Fa l
and
.Dq Fa r ,
and returns an integer less than, equal to, or greater than 0, according to
whether or not
.Dq Fa l
is lexicographically less than, equal to, or greater than
.Dq Fa r
when taken to be unsigned characters (this behaviour is just like that of
.Xr memcmp 3 ) .
.Pp
.Sy NOTE :
.Fn Bitncmp 
assumes 
.Sy network byte order ;
this means that the fourth octet of 
.Li 192.5.5.240/28 
.Li 0x11110000 .
.Sh RETURN VALUES
.Fn Bitncmp
returns values in the manner of
.Xr memcmp 3 :
.Bd -ragged -offset indent
+1 if 
.Dq Fa 1
is greater than 
.Dq Fa r ;
.Pp
-1 if 
.Dq Fa l
is less than 
.Dq Fa r ; 
and
.Pp
0 if 
.Dq Fa l
is equal to
.Dq Fa r ,
.Ed
.Pp
where 
.Dq Fa l
and 
.Dq Fa r
are both interpreted as strings of unsigned characters (through bit 
.Dq Fa n . )
.Sh SEE ALSO
.Xr memcmp 3 .
.Sh AUTHOR
Paul Vixie (ISC).