Unix Shell Syntax History
GNU Double-Dash Syntax, 1990s
in 1990s, the GNU introduced the double-dash syntax, in hope to make unix commands more readable. e.g.
emacs --no-init-file
- Unfortunately, it didn't really catch on.
- Most commands today do offer the double-dash variant, but only for some options.
- The double-dash option does not necessarily mean there's a corresponding single-dash one, and vice versa.
- The end result is just more syntax jumble.
Unix Shell Syntax History, 2000 to 2013
as of , the unix shell tool syntax have gone thru more evolution.
during 2000s, a new syntax form became popular, one that has a Action or Verb keyword immediately following the command name. Here are some prominent examples
apt-get
apt-get install --simulate -y name
Note this line contains 3 elements of syntax: dashless action positional argument, double dash, single dash, and the main argument for the verb name is placed at the end.
git
git add -m"some" fpath
iptables
iptables --table filter --append INPUT --jump DROP
Note this command has a main dish, that is the --table filter, which specifies which table to act on.
It is not a verb nor action.