TALLOC(3N-SVR4)    RISC/os Reference Manual     TALLOC(3N-SVR4)



NAME
     t_alloc - 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 refer-
     enced by the structure.

     The structure to allocate is specified by struct_type, and
     can 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 may subsequently be used as
     an argument to one or more transport functions.

     Each of the above structures, except T_INFO, contains at
     least one field of type struct netbuf.  netbuf is described
     in intro(3).  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:

     T_ADDR    The addr field of the t_bind, t_call, t_unitdata,
               or t_uderr structures.

     T_OPT     The opt field of the t_optmgmt, t_call,
               t_unitdata, or t_uderr structures.

     T_UDATA   The udata field of the t_call, t_discon, or



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TALLOC(3N-SVR4)    RISC/os Reference Manual     TALLOC(3N-SVR4)



               t_unitdata structures.

     T_ALL     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 ini-
     tialize the buf pointer and maxlen [see netbuf in intro(3)
     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 t_open and
     t_getinfo.  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 t_open or t_getinfo), talloc will be unable to
     determine 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 talloc to allocate structures will help ensure the
     compatibility of user programs with future releases of the
     transport interface.

     On failure, t_errno 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(3), t_free(3N), t_getinfo(3N), t_open(3N).

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

















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