Using the detox utility with OCaml?

I would like to use the detox utility (on my Mac) inside OCaml, here is my failed attempt :

In my home directory, I first did mkdir mydir, cd mydir and touch accented\ filename\ àèíóù.txt. Then, inside utop :


In this particular, minimal example, I supposed I could find an adhoc fix by replacing the spaces by "\ ", but obviously I’m looking for a solution that works in all cases.

The second difficulty that I have is with retrieving the output of the detox -n command. If I redo the above example with a non-problematic filename (say easy_filename.txt) instead of accented\ filename\ àèíóù.txt :


There is no error message but the output of the command is not even printed in utop, how could I retrieve it ? Using the stdout channel or perhaps I should create an Ocaml-made executable for this.

You can use Sys.command (Filename.quote_command "detox" ["-n"; the_file]).

The easiest approach is to redirect its output to a file and then read the file. Again with Filename.quote_command you can do this by using the ~stdout (and ~stderr) optional arguments.



In addition to @nojb’s answer (quote if you use Sys.command, or use something the allows passing arguments one by one), I just wanted to mention that the problem here is the spaces in the filename, not the accents. Sys.command uses your shell, which passes “accented”, “filename”, and “àèíóù.txt” as different arguments.

1 Like

And since you mentioned having tried with \, note that you need to double the \ so that it remains
in the final string. Indeed the escape sequence \ denotes a single space:

# Sys.command "ls -l foo\\ bar.txt";;
-rw-rw-r-- 1 kim kim 0 Jun  8 09:06 'foo bar.txt'
- : int = 0

But of course, the right answer is the one given by @nojb to use Filename.quote_command which is much more robust and also handles cmd.exe (Windows command lines).

1 Like