ultrix man page for t_alloc

t_alloc(3xti)															     t_alloc(3xti)

Name
       t_alloc - allocate a library structure

Syntax
       #include <xti.h>

       char *t_alloc(fd, struct_type, fields)
       int fd;
       int struct_type;
       int fields;

Arguments
       fd	 Refers to the transport endpoint through which the newly allocated structure is passed.

       struct_type
		 Specifies  the  allocated  structure  where each structure can subsequently be used as an argument to one or more transport func-
		 tions.

		 The struct_type argument must specify one of the following:
		 T_BIND_STR	     struct	    t_bind
		 T_CALL_STR	     struct	    t_call
		 T_OPTMGMT_STR	     struct	    t_optmgmt
		 T_DIS_STR	     struct	    t_discon
		 T_UNITDATA_STR struct	       t_unitdata
		 T_UDERROR_STR	struct	       t_uderr
		 T_INFO_STR	     struct	    t_info

       fields	 Specifies which buffers to allocate, where the argument is the bitwise-OR of any of the following:

		 T_ADDR      The addr field of the or t_uderr structures (size obtained from info_addr).

		 T_OPT	     The opt field of the t_optmgmt, t_call, t_unitdata, or t_uderr structures (size obtained from info_options).

		 T_UDATA     The udata field of the t_call, t_discon, or t_uderr  structures  (for  T_CALL_STR,  size  is  the	maximum  value	of
			     info_connect  and info_discon; for T_DIS_STR, size is the value of info_discon; for T_UNITDATA_STR, size is the value
			     of info_tsdu).

		 T_ALL	     All relevant fields of the given structure.

Description
       The function dynamically allocates memory for the various transport function argument structures as listed  under  the  ARGUMENTS  section.
       This function allocates memory for the specified structure and also allocates memory for buffers referenced by the structure.

       Each  of the accepted structures, except contains at least one field of type struct netbuf. For each field of this type, the user can spec-
       ify that the buffer for that field should be allocated as well. The length of the  buffer  allocated  is  based	on  the  size  information
       returned in the or

       For each field specified in fields, allocates memory for the buffer associated with the field and initializes the len field to zero and the
       buf pointer and maxlen field accordingly. Because the length of the buffer allocated is based on the same size information that is returned
       to  the	user  on  and fd must refer to the transport endpoint through which the newly allocated structure will be passed. In this way, the
       appropriate size information can be accessed. If the size value associated with any specified field is -1 or -2, will be unable	to  deter-
       mine  the  size of the buffer to allocate and will fail, setting t_errno to [TSYSERR] and errno to [EINVAL]. For any field not specified in
       fields, buf will be set to NULL and maxlen will be set to zero.

       Use of to allocate structures helps to ensure the compatibility of user programs with future releases of the transport interface functions.

       ---------------------------------------
       Parameters    Before Call   After Call
       ---------------------------------------
       fd	     x		   /
       struct_type   x		   /

       fields	     x		   /
       ---------------------------------------

Return Values
       Upon successful completion, returns a pointer to the newly allocated structure. On failure, NULL is returned.

Diagnostics
       On failure, t_errno is set to one of the following:

       [TBADF]		   The specified file descriptor does not refer to a transport endpoint.

       [TNOTSUPPORT]	   This function is not supported by the current implementation of XTI.

       [TSYSERR]	   A system error has occurred during execution of this function.

       [TNOSTRUCTYPE]	   An unsupported struct_type has been requested.

See Also
       t_free(3xti), t_getinfo(3xti), t_open(3xti)

																     t_alloc(3xti)