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MODBUS_MAPPING_NEW(3)          Libmodbus Manual          MODBUS_MAPPING_NEW(3)

NAME
       modbus_mapping_new - allocate four arrays of bits and registers

SYNOPSIS
       modbus_mapping_t modbus_mapping_new(int nb_bits, int nb_input_bits, int
       nb_registers, int nb_input_registers);*

DESCRIPTION
       The modbus_mapping_new() function shall allocate four arrays to store
       bits, input bits, registers and inputs registers. The pointers are
       stored in modbus_mapping_t structure. All values of the arrays are
       initialized to zero.

       If it isn't necessary to allocate an array for a specific type of data,
       you can pass the zero value in argument, the associated pointer will be
       NULL.

       This function is convenient to handle requests in a Modbus
       server/slave.

RETURN VALUE
       The modbus_mapping_new() function shall return the new allocated
       structure if successful. Otherwise it shall return NULL and set errno.

ERRORS
       ENOMEM
           Not enough memory

EXAMPLE
           /* The fist value of each array is accessible from the 0 address. */
           mb_mapping = modbus_mapping_new(BITS_ADDRESS + BITS_NB,
                                           INPUT_BITS_ADDRESS + INPUT_BITS_NB,
                                           REGISTERS_ADDRESS + REGISTERS_NB,
                                           INPUT_REGISTERS_ADDRESS + INPUT_REGISTERS_NB);
           if (mb_mapping == NULL) {
               fprintf(stderr, "Failed to allocate the mapping: %s\n",
                       modbus_strerror(errno));
               modbus_free(ctx);
               return -1;
           }

SEE ALSO
       modbus_mapping_free(3)

AUTHORS
       The libmodbus documentation was written by Stephane Raimbault
       <stephane.raimbault@gmail.com[1]>

NOTES
        1. stephane.raimbault@gmail.com
           mailto:stephane.raimbault@gmail.com

libmodbus 3.1.0                   10/06/2013             MODBUS_MAPPING_NEW(3)