modbus_set_error_recovery.txt
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modbus_set_error_recovery(3)
============================
NAME
----
modbus_set_error_recovery - set the error recovery mode
SYNOPSIS
--------
*int modbus_set_error_recovery(modbus_t *'ctx', int 'enabled');*
DESCRIPTION
-----------
The _modbus_set_error_recovery()_ function shall set the error recovery mode to
apply when the connection fails.
By default there is no error recovery so the application must check the error
values returned by libmodbus functions and handle them if necessary.
When enabled, the library will attempt an immediate reconnection which may hang
for several seconds if the network to the remote target unit is down. The write
will try a infinite close/connect loop until to be successful and the
select/read calls will just try to retablish the connection one time then will
return an error (if the connecton was down, the values to read are certainly not
available anymore after reconnection, except for slave/server).
It's not recommanded to enable error recovery for slave/server.
RETURN VALUE
------------
The _modbus_close()_ function shall return 0 if successful. Otherwise it shall
return -1 and set errno to one of the values defined below.
ERRORS
------
*EINVAL*::
The value of the argument 'enabled' is not 'TRUE' of 'FALSE'.
AUTHORS
-------
The libmodbus documentation was written by Stéphane Raimbault
<stephane.raimbault@gmail.com>