ls from GNU core utilities. The manual page only mentions
always, but I find that
tty also works. This option doesn't seem to be used widely, but still it was mentioned here and there. Is it a deprecated alias of
auto? If not, what's the difference between
auto? When shall I use them respectively?
There is no difference.
Looking at the sources:
alwayscan be used interchangeably with
nevercan be used interchangeably with
autocan be used interchangeably with
They are all GNU-isms. :)