How to get list of directories in Lua

Question

I need a list of directory in LUA

Suppose I have a directory path as "C:\\Program Files"

I need a list of all the folders in that particular path and

Answer 1

Take the easy way, install lfs. Then use the following constructs to find what you need:

require'lfs'
for file in lfs.dir[[C:\Program Files]] do
    if lfs.attributes(file,"mode") == "file" then print("found file, "..file)
    elseif lfs.attributes(file,"mode")== "directory" then print("found dir, "..file," containing:")
        for l in lfs.dir("C:\\Program Files\\"..file) do
             print("",l)
        end
    end
end

notice that a backslash equals [[\]] equals "\\", and that in windows / is also allowed if not used on the cmd itself (correct me if I'm wrong on this one).

Answer 2

I hate having to install libraries (especially those that want me to use installer packages to install them). If you're looking for a clean solution for a directory listing on an absolute path in Lua, look no further.

Building on the answer that sylvanaar provided, I created a function that returns an array of all the files for a given directory (absolute path required). This is my preferred implementation, as it works on all my machines.

-- Lua implementation of PHP scandir function
function scandir(directory)
    local i, t, popen = 0, {}, io.popen
    local pfile = popen('ls -a "'..directory..'"')
    for filename in pfile:lines() do
        i = i + 1
        t[i] = filename
    end
    pfile:close()
    return t
end

If you are using Windows, you'll need to have a bash client installed so that the 'ls' command will work - alternately, you can use the dir command that sylvanaar provided:

'dir "'..directory..'" /b /ad'