cat.lua

local args = { ... }

if #args == 0 then
    print("Usage: cat <filename>")
    return
end

local filename = args[1]
local file = fs.open(filename, 'r')

if not file then
    print("File not dound: " .. filename)
    return
end

local content = file.readAll()
file.close()
print(content)