How to make the linux/macOS command " .ls >> files.txt " run at php using exec()?

I Just wanna to list all files and subdirectories and store this list in file ... in MS-DOS, Linux and MAC OS, the command line -- .ls( or .dir) >> files.txt -- would give me what I want ... But, how to make a php script run it ?

if I use (on php)

exec ('ls >> files.txt');

I will get a error like this: Warning: Unexpected character in input: '' (ASCII=28) state=0 in /Applications/XAMPP/xamppfile开发者_开发问答s/htdocs/DjUtilities/makeLabels.php on line 29

...

please, any idea ???

The use of this will be to set labels with the musics in a cd, here, divided by directories... I wanna to get any cd's (subdirectories) and list the files (the tracks) to make a label with the track list....

So, The initial idea was to create a file with these data and then, process the data to make the labels... any better way to do that will be very welcome !!

You can use 'opendir' and 'readdir' to do that, both native php commands...

It's not up to your 'exec(...)' code. Same code runs well in my environment.

<?php
exec('ls >> filelist.txt');
?>

And It's result.

$ cat filelist.txt 
a.html
a.out
...(omitted)

So, It looks like your php file may has some weird syntax/characters on line 29. ( like wrong usage of backslashes )