.\"
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD$
.\"
.Dd July 9, 2001
.Dt UCRED 9
.Os
.Sh NAME
.Nm ucred ,
.Nm crget ,
.Nm crhold ,
.Nm crfree ,
.Nm crshared ,
.Nm crcopy ,
.Nm crdup
.Nd "functions related to user credentials"
.Sh SYNOPSIS
.In sys/param.h
.In sys/ucred.h
.Ft "struct ucred *"
.Fn crget void
.Ft void
.Fn crhold "struct ucred *cr"
.Ft void
.Fn crfree "struct ucred *cr"
.Ft int
.Fn crshared "struct ucred *cr"
.Ft void
.Fn crcopy "struct ucred *dest" "struct ucred *src"
.Ft "struct ucred *"
.Fn crdup "struct ucred *cr"
.Sh DESCRIPTION
The
.Nm
family of functions is used to manage user credential structures
.Pq Vt "struct ucred"
within the kernel.
.Pp
The
.Fn crget
function allocates memory
for a new structure, sets its reference count to 1, and
initializes its lock.
.Pp
The
.Fn crhold
function increases the reference count on the credential.
.Pp
The
.Fn crfree
function decreases the reference count on the credential.
If the count drops to 0, the storage for the structure is freed.
.Pp
The
.Fn crshared
function returns true if the credential is shared.
A credential is considered to be shared if its reference
count is greater than one.
.Pp
The
.Fn crcopy
function copies the contents of the source (template)
credential into the destination template.
The
.Vt uidinfo
structure within the destination is referenced
by calling
.Xr uihold 9 .
.Pp
The
.Fn crdup
function allocates memory for a new structure and copies the
contents of
.Fa cr
into it.
The actual copying is performed by
.Fn crcopy .
.Sh RETURN VALUES
The functions that return values all return a pointer to a
.Vt ucred
structure.
.Sh SEE ALSO
.Xr uihold 9
.Sh AUTHORS
This man page was written by
.An Chad David Aq davidc@acns.ab.ca .