luaJIT error handling with FFI calls a non-existent method

Question

What I want to avoid is to capture/ignore the exception when FFI calls a non-existent method.

For example, the following code calls the non_existent_method. However, pcall cannot handle the error.

local ffi = require "ffi"
local C = ffi.C

ffi.cdef [[
    int non_existent_method(int num);
]]

local ok, ret = pcall(C.non_existent_method, 1)

if not ok then
    return
end

I got the following error with OpenResty/lua-nginx-module.

lua entry thread aborted: runtime error: dlsym(RTLD_DEFAULT, awd): symbol not found

Answer 1

One possible solution would be wrapping the C.non_existent_method call with a lua function.

For example

local ok, ret = pcall(function()
    return C.non_existent_method(len)
end)

if not ok then
    ......
end