sudo chmod 666 /dev/ttyACM0 si tu veux que tout le monde puisse lire et écrire sur le point cité dans la commande
pour ta gouverne voici la référence UNIX que tu peux trouver très facilement sur Internet
chmod 666 file/folder means that all users can read and write but cannot execute the file/folder;
chmod 777 file/folder allows all actions for all users;
chmod 744 file/folder allows only user (owner) to do all actions; group and other users are allowed only to read.
permission to: user(u) group(g) other(o)
/¯¯¯\ /¯¯¯\ /¯¯¯\
octal: 6 6 6
binary: 1 1 0 1 1 0 1 1 0
what to permit: r w x r w x r w x
binary - 1: enabled, 0: disabled
what to permit - r: read, w: write, x: execute
permission to - user: the owner that create the file/folder
group: the users from group that owner is member
other: all other users