lua-shmem

Low-level Lua convenience wrapper for IPC shared memory functionality. Wraps calls to mmap/munmap to create and free shared memory, and memset/memcpy calls to write and clear the shared memory area.

Installation

$ luarocks install lua-shmem

From source:

$ gcc -shared -o shmem.o src/shmem.c -llua

Example

local shmem = require("shmem")

local mem = shmem.new(1024) -- 1 KiB shared memory
mem:write("hello world")
print(mem:read()) -- hello world

API

Function	Returns	Description
shmem.new(size:number)	shmem	Creates new shared memory area of size bytes.
shmem:free()	boolean, number	Frees shared memory area. Returns true if successful, false and error code if not.
shmem:write(data:string)	None	Copies data to start of shared memory.
shmem:fill(data:string[, fill:number])	None	Copies data to shared memory and pads the rest of the memory area with fill or 0.
shmem:clear()	None	Fills entire shared memory area with 0.
shmem:read()	string	Reads contents of shared memory.

TODO

• Cursor-based write to non-start positions in memory similar to Lua's io