# Directory file tree & \`walkdir()\`

**URL:** <https://discourse.julialang.org/t/directory-file-tree-walkdir/27768>\
**Category:** New to Julia\
**Created:** [August 20, 2019, 4:35pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768 "2019-08-20T16:35:08Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![BLI](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bli/32/37206_2.png) [@BLI](https://discourse.julialang.org/u/BLI)\
**Post date:** [August 20, 2019, 4:35pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768/1 "2019-08-20T16:35:08Z")

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I’m trying to make some Julia code for (i) generating a directory/file tree at a given directory, and (ii) write the result to a CSV file.

The use case is that I have ripped my movie disks to my hard disk (no pirate copying!; I’ve purchased every disk) so that I can stream my movies from a hard disk. I need an overview of my movies so that I don’t buy movies I already own…

I’ve made some code (I will turn it into a function when I’m happy with it), so that I can run it regularly to update/generate a recent list. I’m sure the code can be made more elegant… so I’m open to suggestions (and to learn):

```julia
julia> using DelimitedFiles
julia> cd("e:/video")

```

My code is as follows:

```julia
file_tree = []
header = "File Tree"
file_extension = false
for (root, dirs, files) in walkdir(".")
    root_vec = split(root,"\\")
    root_name = "Folder: "*root_vec[end]
    root_length = length(root_vec)
    dir_string = fill("",root_length)
    dir_string[end] = root_name
    push!(file_tree,dir_string)
    #
    for file in files
        if file_extension
            file_name = file
        else
            file_name = splitext(file)[1]
        end
        file_string = fill("",root_length+1)
        file_string[end] = file_name
        push!(file_tree,file_string)   
    end
end
if header == ""
    popfirst!(file_tree)
else
    file_tree[1] = [header]
end
for i in 2:length(file_tree)
    popfirst!(file_tree[i])
end

```

I then save the resulting file tree to file:

```julia
julia> open("files.txt","w")
julia> writedlm("files.txt",file_tree,"\t");

```

OK… this works, and produces the following tree view (in an ASCII editor; setting `file_extension = true`):

 ![image](https://global.discourse-cdn.com/julialang/original/3X/3/b/3bb2d414636c4afef4cb5dfcaea902759ec4251a.png)

Questions:

1. Is there a more elegant/compact way to do this?
2. Can I read the file size from `walkdir()` – so that I can decide whether it is a DVD or BD movie?
3. Is there a way to _close_ the file I open using `DelimitedFiles` (on Windows 10) – without restarting the computer?

---

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**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [August 20, 2019, 4:46pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768/2 "2019-08-20T16:46:35Z")

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You can use `filesize(stat(file_name))` to get the number of bytes in the file named `file_name`. And you can call `close()` on the output of `open()` to close a file.

Even better, there is no need to call `close()` manually if you use the `do`-block version of open, like this:

```julia
julia> data = rand(2, 3)
2×3 Array{Float64,2}:
 0.548722 0.761118 0.876877
 0.78785 0.00870406 0.561466

julia> using DelimitedFiles

julia> open("out.csv", "w") do f
         writedlm(f, data)
       end

```

Using `open()` in this way will ensure that the file is closed automatically.

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<div class="post-metadata">

**Author:** ![BLI](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bli/32/37206_2.png) [@BLI](https://discourse.julialang.org/u/BLI)\
**Post date:** [August 20, 2019, 5:22pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768/3 "2019-08-20T17:22:24Z")

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What is the `f` in the `do f ... end`? Is it a typo — shouldn’t be there?

And — is the alternative:

```julia
julia> file = open("out.csv","w")
...
julia> close(file)?

```

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<div class="post-metadata">

**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [August 20, 2019, 5:29pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768/4 "2019-08-20T17:29:53Z")

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It’s not a typo-- the `f` is a variable which gets bound to the open file. Check out [Functions · The Julia Language](https://docs.julialang.org/en/v1/manual/functions/index.html#Do-Block-Syntax-for-Function-Arguments-1) for a description of what’s going on.

And yes, that’s roughly the alternative, except: in your case, what happens if an error is thrown before the `close(file)` line? You want the file to be closed no matter what, so you might instead write something like:

```julia
file = open(...)
try 
  ...
finally
  close(file)
end

```

the `open(...) do f` method of `open()` takes care of all that for you.

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<div class="post-metadata">

**Author:** ![BLI](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bli/32/37206_2.png) [@BLI](https://discourse.julialang.org/u/BLI)\
**Post date:** [August 20, 2019, 6:04pm UTC](https://discourse.julialang.org/t/directory-file-tree-walkdir/27768/5 "2019-08-20T18:04:11Z")

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Thanks!