T_FREE(3NSL) Networking Services Library Functions T_FREE(3NSL)
NAME
t_free - free a library structure
SYNOPSIS
#include <xti.h>
int t_free(
void *ptr,
int struct_type);
DESCRIPTION
This routine is part of the
XTI interfaces which evolved from the
TLI interfaces.
XTI represents the future evolution of these interfaces.
However,
TLI interfaces are supported for compatibility. When using a
TLI routine that has the same name as an
XTI routine, the
tiuser.h header
file must be used. Refer to the
TLI COMPATIBILITY section for a
description of differences between the two interfaces.
The
t_free() function frees memory previously allocated by
t_alloc(3NSL).
This function will free memory for the specified structure, and will also
free memory for buffers referenced by the structure.
The argument
ptr points to one of the seven structure types described for
t_alloc(3NSL), and
struct_type identifies the type of that structure
which must be one of the following:
T_BIND struct t_bind
T_CALL struct t_call
T_OPTMGMT struct t_optmgmt
T_DIS struct t_discon
T_UNITDATA struct t_unitdata
T_UDERROR struct t_uderr
T_INFO struct t_info
where each of these structures is used as an argument to one or more
transport functions.
The function
t_free() will check the
addr,
opt and
udata fields of the
given structure, as appropriate, and free the buffers pointed to by the
buf field of the
netbuf structure. If
buf is a null pointer,
t_free() will not attempt to free memory. After all buffers are freed,
t_free() will free the memory associated with the structure pointed to by
ptr.
Undefined results will occur if
ptr or any of the
buf pointers points to
a block of memory that was not previously allocated by
t_alloc(3NSL).
RETURN VALUES
Upon successful completion, a value of
0 is returned. Otherwise, a
value of -1 is returned and
t_errno is set to indicate an error.
VALID STATES
ALL - apart from
T_UNINIT.
ERRORS
On failure,
t_errno is set to the following:
TNOSTRUCTYPE Unsupported
struct_type requested.
TPROTO This error indicates that a communication problem has
been detected between XTI and the transport provider for
which there is no other suitable XTI error
(t_errno).
TSYSERR A system error has occurred during execution of this
function.
TLI COMPATIBILITY
The
XTI and
TLI interface definitions have common names but use different
header files. This, and other semantic differences between the two
interfaces are described in the subsections below.
Interface Header
The
XTI interfaces use the header file,
xti.h.
TLI interfaces should
not use this header. They should use the header:
#include <tiuser.h>
Error Description Values
The
t_errno value that can be set by the
XTI interface and cannot be set
by the
TLI interface is:
TPROTOATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT Level | Safe |
+---------------+-----------------+
SEE ALSO
t_alloc(3NSL),
attributes(7) May 7, 1998
T_FREE(3NSL)