modbus_get_header_length - retrieve the current header length

       The libmodbus documentation was written by Stéphane Raimbault <stephane.raimbault@gmail.com>

libmodbus v3.1.6                                   12/09/2019                            MODBUS_GET_HEADER_LE(3)

       The modbus_get_header_length() function shall retrieve the current header length from the backend. This
       function is convenient to manipulate a message and so its limited to low-level operations.

       modbus_get_header_length - retrieve the current header length

       The header length as integer value.

libmodbus(7)

intmodbus_get_header_length(modbus_t*ctx);