14 Dec
2022
14 Dec
'22
8:38 a.m.
Hi,
Now who told tar and ps that they don't need the dash? ;-)
Someone who created the dash to show the argument contained optional options rather than a filename. If they're not optional then the dash isn't required. :-)
I'll give that to you for tar, but the options are ps are, in fact, optional.
True. So I should have said the dash is distinguish options from possible following arguments which would otherwise look like options. Depending on the ps(1), either all its arguments are options or their values, or process IDs are also allowed and since no dash-less option starts with a digit it can't be confused. -- Cheers, Ralph.