Problem with multiple master read

[Behzad Yahosseini]

Hello

I'm new to libmodbus and I recently use it for my project.

I have a problem with modbus client in  TCP mode.

my platform is raspberry pi zero with Linux raspbian 4.9 stretch.

I try to use multiple connection from my modbus tcp client program and read from multiple servers

here is my code:

----------------------------

modbus_t * ctx0;
modbus_t * ctx1;
modbus_t * ctx2;


Read_0xxxx_bits = (uint8_t *) malloc(10 * sizeof(uint8_t));
memset(Read_0xxxx_bits, 0, 10 * sizeof(uint8_t));


Read_3xxxx_registers = (uint16_t *) malloc(10 * sizeof(uint16_t));
memset(Read_3xxxx_registers, 0, 10 * sizeof(uint16_t));


Read_4xxxx_registers = (uint16_t *) malloc(10 * sizeof(uint16_t));
memset(Read_4xxxx_registers, 0, 10 * sizeof(uint16_t));


for(i=0;i<2;i++)
{
 switch(i)
 {
 case(0):
 ctx0 = modbus_new_tcp("192.168.10.10","502");
 modbus_set_debug(ctx0, TRUE);
 modbus_connect(ctx0);
 break;
 case(1):
 ctx1 = modbus_new_tcp("192.168.10.11","502");
 modbus_set_debug(ctx1, TRUE);
 modbus_connect(ctx1);
 break;
 case(2):
 ctx2 = modbus_new_tcp("192.168.10.12","502");
 modbus_set_debug(ctx2, TRUE);
 modbus_connect(ctx2);
 break;
 }
}


modbus_read_bits(ctx0,0,10, Read_0xxxx_bits);

modbus_read_input_registers(ctx1, 0, 10, Read_3xxxx_registers );

modbus_read_registers(ctx2, 0, 10, Read_4xxxx_registers);

modbus_close(ctx0);
modbus_close(ctx1);
modbus_close(ctx2);

modbus_free(ctx0);
modbus_free(ctx1);
modbus_free(ctx2);

-------------------------------------------------------------

strange thing happens:

there is only one of the connection (ctx2) is successful and all three of the request go to the ctx2 server!

the reason that I want to stay connected to all my server is because my servers do not handle socket disconnection well and still stay connected for a long time and leave socket in "FIN_WAIT2"  statuse

I try to use a modbys_t * array but the result was the same.

would you please help me on this?

Best regards