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.\" $Id: krb5_data.3 20040 2007-01-23 20:35:12Z lha $
.\"
.Dd Jan 23, 2007
.Dt KRB5_DATA 3
.Os HEIMDAL
.Sh NAME
.Nm krb5_data ,
.Nm krb5_data_zero ,
.Nm krb5_data_free ,
.Nm krb5_free_data_contents ,
.Nm krb5_free_data ,
.Nm krb5_data_alloc ,
.Nm krb5_data_realloc ,
.Nm krb5_data_copy ,
.Nm krb5_copy_data ,
.Nm krb5_data_cmp
.Nd operates on the Kerberos datatype krb5_data
.Sh LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
.Sh SYNOPSIS
.In krb5.h
.Pp
.Li "struct krb5_data;"
.Ft void
.Fn krb5_data_zero "krb5_data *p"
.Ft void
.Fn krb5_data_free "krb5_data *p"
.Ft void
.Fn krb5_free_data_contents "krb5_context context" "krb5_data *p"
.Ft void
.Fn krb5_free_data "krb5_context context" "krb5_data *p"
.Ft krb5_error_code
.Fn krb5_data_alloc "krb5_data *p" "int len"
.Ft krb5_error_code
.Fn krb5_data_realloc "krb5_data *p" "int len"
.Ft krb5_error_code
.Fn krb5_data_copy "krb5_data *p" "const void *data" "size_t len"
.Ft krb5_error_code
.Fn krb5_copy_data "krb5_context context" "const krb5_data *indata" "krb5_data **outdata"
.Ft krb5_error_code
.Fn krb5_data_cmp "const krb5_data *data1" "const krb5_data *data2"
.Sh DESCRIPTION
The
.Li krb5_data
structure holds a data element.
The structure contains two public accessible elements
.Fa length
(the length of data)
and
.Fa data
(the data itself).
The structure must always be initiated and freed by the functions
documented in this manual.
.Pp
.Fn krb5_data_zero
resets the content of
.Fa p .
.Pp
.Fn krb5_data_free
free the data in
.Fa p
and reset the content of the structure with
.Fn krb5_data_zero .
.Pp
.Fn krb5_free_data_contents
works the same way as
.Fa krb5_data_free .
The diffrence is that krb5_free_data_contents is more portable (exists
in MIT api).
.Pp
.Fn krb5_free_data
frees the data in
.Fa p
and
.Fa p
itself.
.Pp
.Fn krb5_data_alloc
allocates
.Fa len
bytes in
.Fa p .
Returns 0 or an error.
.Pp
.Fn  krb5_data_realloc
reallocates the length of
.Fa p
to the length in
.Fa len .
Returns 0 or an error.
.Pp
.Fn krb5_data_copy
copies the
.Fa data
that have the length
.Fa len
into
.Fa p .
.Fa p
is not freed so the calling function should make sure the
.Fa p
doesn't contain anything needs to be freed.
Returns 0 or an error.
.Pp
.Fn krb5_copy_data
copies the
.Li krb5_data
in
.Fa indata
to
.Fa outdata .
.Fa outdata
is not freed so the calling function should make sure the
.Fa outdata
doesn't contain anything needs to be freed.
.Fa outdata
should be freed using
.Fn krb5_free_data .
Returns 0 or an error.
.Pp
.Fn krb5_data_cmp
will compare two data object and check if they are the same in a
simular way as memcmp does it.  The return value can be used for
sorting.
.Sh SEE ALSO
.Xr krb5 3 ,
.Xr krb5_storage 3 ,
.Xr kerberos 8