Linux Simple I/O Library

libsimpleio is an attempt to encapsulate (as much as possible) the ugliness of Linux I/O device access. It provides services for the following types of I/O devices:

Industrial I/O Subsystem A/D (Analog to Digital) Converter Devices
Industrial I/O Subsystem D/A (Digital to Analog) Converter Devices
GPIO (General Purpose Input/Output) Pins
Raw HID (Human Interface Device) Devices
I²C (Inter-Integrated Circuit) Bus Devices
Labview LINX Remote I/O Devices
PWM (Pulse Width Modulated) Output Devices
Remote I/O Protocol Devices
Serial Ports
SPI (Serial Peripheral Interface) Bus Devices
Stream Framing Protocol Devices
TCP and UDP over IPv4 Network Devices
Watchdog Timer Devices

Although libsimpleio was originally intended for Linux microcomputers such as the Raspberry Pi, it can also be useful on larger desktop Linux systems.

The C wrapper functions exported by libsimpleio all follow the same uniform pattern:

All C wrapper functions are proper procedures (void f() in C).
All input arguments of primitive types (int, float, etc.) are passed by value.
All output arguments of primitive types are passed by reference (int *, float *, etc.).
All composite types are passed by reference.
int32_t is used wherever possible for int and bool arguments.

All of the C wrapper functions are declared between _BEGIN_STD_C and _END_STD_C for C++. Additional source code libraries are provided for Ada, C++, C#, Free Pascal, Modula-2, and Python that define OOP (Object Oriented Programming) thick binding classes for libsimpleio.