# modbus_connect(3) Manual Page

## NAME

modbus_connect - establish a Modbus connection

## SYNOPSIS

int modbus_connect(modbus_t *ctx);

## DESCRIPTION

The modbus_connect() function shall etablish a connection to a Modbus server, a network or a bus using the context information of libmodbus context given in argument.

## RETURN VALUE

The modbus_connect() function shall return 0 if successful. Otherwise it shall return -1 and set errno to one of the values defined by the system calls of the underlying platform.

## EXAMPLE

    modbus_t *ctx;

    ctx = modbus_new_tcp("127.0.0.1", 502);
    if (modbus_connect(ctx) == -1) {
        fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno));
        modbus_free(ctx);
        return -1;
    }

## SEE ALSO

modbus_close(3)

## AUTHORS

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