modbus_reply(3)

1MODBUS_REPLY(3)                Libmodbus Manual                MODBUS_REPLY(3)
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NAME

6       modbus_reply - send a reponse to the received request
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SYNOPSIS

9       *int modbus_reply(modbus_t *ctx, const uint8_t *req, int req_length,
10       modbus_mapping_t *mb_mapping);
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DESCRIPTION

13       The modbus_reply() function shall send a response to received request.
14       The request req given in argument is analyzed, a response is then built
15       and sent by using the information of the modbus context ctx.
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17       If the request indicates to read or write a value the operation will
18       done in the modbus mapping mb_mapping according to the type of the
19       manipulated data.
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21       If an error occurs, an exception response will be sent.
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23       This function is designed for Modbus server.
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RETURN VALUE

26       The modbus_reply() function shall return the length of the response
27       sent if successful. Otherwise it shall return -1 and set errno.
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ERRORS

30       EMBMDATA
31           Sending has failed
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33       See also the errors returned by the syscall used to send the response
34       (eg. send or write).
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AUTHORS

40       The libmodbus documentation was written by Stéphane Raimbault
41       <stephane.raimbault@gmail.com[1]>
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NOTES

44        1. stephane.raimbault@gmail.com
45           mailto:stephane.raimbault@gmail.com
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49libmodbus 3.0.8                   07/31/2019                   MODBUS_REPLY(3)