t_free(3N)

NAME

t_free − free a library structure

SYNOPSIS

cc [ flag ... ] file ... −lnsl [ library ... ]

#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, a different header file, tiuser.h , must be used. Refer to the section, TLI COMPATIBILITY , for a description of differences between the two interfaces.

The t_free() function frees memory previously allocated by t_alloc(3N). This function will free memory for the specified structure, and will also free memory for buffers referenced by the structure.

ptr points to one of the seven structure types described for t_alloc(), 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.

(buf and other members of the netbuf structure are shown in t_connect(3N).) 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().

VALID STATES

Legitimate states (see t_getstate(3N)) for a call to this routine are every one except T_UNINIT .

RETURN VALUES

t_free() returns:

0 On success.

−1 On failure.

On failure, t_errno is set to indicate the error, and possibly errno is set.

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 t_errno value.

TSYSERR A system error has occurred during execution of this function, errno will be set to the specific error.

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:

TPROTO

For more information refer to the Transport Interfaces Programming Guide.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
MT-Level	MT-Safe

Museum

Related Articles