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MODBUS_NEW_TCP_PI(3)	       libmodbus Manual		  MODBUS_NEW_TCP_PI(3)

NAME
       modbus_new_tcp_pi - create a libmodbus context for TCP Protocol
       Independent

SYNOPSIS
       modbus_t	*modbus_new_tcp_pi(const char *node, const char	*service);

DESCRIPTION
       The modbus_new_tcp_pi() function	shall allocate and initialize a
       modbus_t	structure to communicate with a	Modbus TCP IPv4	or IPv6
       server.

       The node	argument specifies the host name or IP address of the host to
       connect to, eg. "192.168.0.5" , "::1" or	"server.com". A	NULL value can
       be used to listen any addresses in server mode.

       The service argument is the service name/port number to connect to. To
       use the default Modbus port use the string "502". On many Unix systems,
       it's convenient to use a	port number greater than or equal to 1024
       because it's not	necessary to have administrator	privileges.

RETURN VALUE
       The function shall return a pointer to a	modbus_t structure if
       successful. Otherwise it	shall return NULL and set errno	to one of the
       values defined below.

ERRORS
       EINVAL
	   The node string is empty or has been	truncated. The service string
	   is empty or has been	truncated.

EXAMPLE
	   modbus_t *ctx;

	   ctx = modbus_new_tcp_pi("::1", "1502");
	   if (ctx == NULL) {
	       fprintf(stderr, "Unable to allocate libmodbus context\n");
	       return -1;
	   }

	   if (modbus_connect(ctx) == -1) {
	       fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno));
	       modbus_free(ctx);
	       return -1;
	   }

SEE ALSO
       modbus_new_tcp(3) modbus_tcp_pi_listen(3) modbus_free(3)

AUTHORS
       The libmodbus documentation was written by StA(C)phane Raimbault
       <stephane.raimbault@gmail.com>

libmodbus v3.1.4		  04/29/2017		  MODBUS_NEW_TCP_PI(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLE | SEE ALSO | AUTHORS

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