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 how to search any particular folder in that list.

Example

Need a list of all the folder in path "C:\Program Files"

Below are folder name in the above path

1. test123

2. test4567

3. folder 123

4. folder 456

5. folder 456 789

   Need to get the above in a list and then have to search for a particular string like folder 456 in folder 456 789 only.

Have Tried below code. Something I am missing below:-

local function Loc_Lines( str )
--
local ret= {}   -- 0 lines

while str do
    local _,_,line,tail= string.find( str, "(.-)\n(.+)" )
    table.insert( ret, line or str )
    str= tail
  Print (str)
end

return ret
end


local function Loc_ShellCommand( cmd )
--
local str= nil

    --
    local f= io.popen( cmd )    -- no command still returns a handle :(
     if f then

        str= f:read'*a'
    Print(str)
        f:close()
    end
    
    if str=="" then   -- take no output as a failure (we can't tell..)
    Print("hi")
        str= nil
    end
 
-- Remove terminating linefeed, if any (eases up one-line analysis)
--
if str then
    if string.sub( str, -1 ) == '\n' then
        str= string.sub( str, 1, -2 )
    end
end

return str
 end


 local function Loc_DirCmd( cmd )

 Print(cmd)

  local str= Loc_ShellCommand( cmd )



 return Loc_Lines(str)
 end


local function Loc_DirList( dirname )

 local ret= {}
  
    local lookup= {}

   local tbl= Loc_DirCmd( "dir /AD /B "..dirname )   -- only dirs

    -- Add slash to every dir line
    --
    for i,v in ipairs(tbl) do
        table.insert( ret, v..'\\' )
        lookup[v]= true
    end       

    
    -- Return with forward slashes
    --
    if true then
        for i=1,table.getn(ret) do
            ret[i]= string.gsub( ret[i], '\\', '/' )
     Print (ret[i])
        end
    end
  

   return ret
 end


 Loc_DirList("C:\\Program Files\\")

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).