OpenBSD-4.6/share/man/man9/hashinit.9

.\"	$OpenBSD: hashinit.9,v 1.4 2007/05/31 19:20:00 jmc Exp $
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.Dd $Mdocdate: May 31 2007 $
.Dt HASHINIT 9
.Os
.Sh NAME
.Nm hashinit
.\" This should be ported from netbsd as well...
.\" .Nm hashdone
.Nd kernel hashtable functions
.Sh SYNOPSIS
.Fd #include <sys/systm.h>
.Ft void *
.Fn hashinit "int num" "int type" "int flags" "u_long *mask"
.Sh DESCRIPTION
The
.Fn hashinit
function is used to allocate a hashtable of a desired size given by the
.Fa num
argument.
The
.Fn hashinit
function will round this number to the next power of two, and
allocate and initialize the requested hashtable.
The
.Fa type
and
.Fa flags
arguments are passed to the
.Xr malloc 9
function unchanged.
The
.Fa mask
argument is used to pass back the mask for use with the allocated
hashing table.
For an example of its use, see
.Xr hash 9 .
.Sh RETURN VALUES
The
.Fn hashinit
function returns a pointer to the allocated and initialized hash table.
.Sh SEE ALSO
.Xr free 9 ,
.Xr hash 9 ,
.Xr malloc 9
.Sh LIMITATIONS
The
.Fn hashinit
function currently only allocates hash tables with LIST bucket pointers
at this time.
Future enhancements to allocate QUEUE bucket pointers may be warranted.
This may necessitate an API change to accommodate.
.Sh HISTORY
The
.Nm
function first appeared in
.Bx 4.4 .