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.\" $Id: krb5_principal_get_realm.3,v 1.6 2003/04/16 13:58:17 lha Exp $
.\"
.Dd June 20, 2001
.Dt KRB5_PRINCIPAL_GET_REALM 3
.Os HEIMDAL
.Sh NAME
.Nm krb5_principal_get_realm ,
.Nm krb5_principal_get_comp_string
.Nd decompose a principal
.Sh LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
.Sh SYNOPSIS
.In krb5.h
.Ft "const char *"
.Fn krb5_principal_get_realm "krb5_context context" "krb5_principal principal"
.Ft "const char *"
.Fn krb5_principal_get_comp_string "krb5_context context" "krb5_principal principal" "unsigned int component"
.Sh DESCRIPTION
These functions return parts of the
.Fa principal ,
either the realm or a specific component. The returned string points
to data inside the principal, so they are valid only as long as the
principal exists.
.Pp
The
.Fa component
argument to
.Fn krb5_principal_get_comp_string
is the component number to return, from zero to the total number of
components minus one. If a the requested component number is out of range,
.Dv NULL
is returned.
.Pp
These functions can be seen as a replacement for the
.Fn krb5_princ_realm ,
.Fn krb5_princ_component
and related macros, described as intermal in the MIT API
specification. A difference is that these functions return strings,
not
.Dv krb5_data .
A reason to return
.Dv krb5_data
was that it was believed that principal components could contain
binary data, but this belief was unfounded, and it has been decided
that principal components are infact UTF8, so it's safe to use zero
terminated strings.
.Pp
It's generally not necessary to look at the components of a principal.
.Sh SEE ALSO
.Xr krb5_unparse_name 3