t_alloc(3N)       UNIX System V(Networking Support Utilities)       t_alloc(3N)


NAME
      talloc - allocate a library structure

SYNOPSIS
      #include <tiuser.h>

      char *talloc(fd, structtype, fields)
      int fd;
      int structtype;
      int fields;

DESCRIPTION
      The talloc function dynamically allocates memory for the various
      transport function argument structures as specified below.  This function
      will allocate memory for the specified structure, and will also allocate
      memory for buffers referenced by the structure.

      The structure to allocate is specified by structtype, and can be one of
      the following:

      TBIND           struct tbind

      TCALL           struct tcall

      TOPTMGMT        struct toptmgmt

      TDIS            struct tdiscon

      TUNITDATA       struct tunitdata

      TUDERROR        struct tuderr

      TINFO           struct tinfo

      where each of these structures may subsequently be used as an argument to
      one or more transport functions.

      Each of the above structures, except TINFO, contains at least one field
      of type struct netbuf.  netbuf is described in intro(3N).  For each field
      of this type, the user may specify that the buffer for that field should
      be allocated as well.  The fields argument specifies this option, where
      the argument is the bitwise-OR of any of the following:

      TADDR    The addr field of the tbind, tcall, tunitdata, or tuderr
                structures.

      TOPT     The opt field of the toptmgmt, tcall, tunitdata, or tuderr
                structures.

      TUDATA   The udata field of the tcall, tdiscon, or tunitdata
                structures.



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t_alloc(3N)       UNIX System V(Networking Support Utilities)       t_alloc(3N)


      TALL     All relevant fields of the given structure.

      For each field specified in fields, talloc will allocate memory for the
      buffer associated with the field, and initialize the buf pointer and
      maxlen [see netbuf in intro(3N) for description of buf and maxlen] field
      accordingly.  The length of the buffer allocated will be based on the
      same size information that is returned to the user on topen and
      tgetinfo.  Thus, fd must refer to the transport endpoint through which
      the newly allocated structure will be passed, so that the appropriate
      size information can be accessed.  If the size value associated with any
      specified field is -1 or -2 (see topen or tgetinfo), talloc will be
      unable to determine the size of the buffer to allocate and will fail,
      setting terrno 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 talloc to allocate structures will help ensure the compatibility
      of user programs with future releases of the transport interface.

      On failure, terrno may be set to one of the following:

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

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

SEE ALSO
      intro(3N), tfree(3N), tgetinfo(3N), topen(3N)
      Programmer's Guide:  Networking Interfaces

DIAGNOSTICS
      On successful completion, talloc returns a pointer to the newly
      allocated structure.  On failure, NULL is returned.




















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