Concept : Command Syntax

Basic


The Empire Shell (command interpreter) expects input in the form:
[##:##] Command : VERB ARG1 ARG2 ...

VERB is any one of the Empire commands on the command list (what you see when you type list-- e.g. , info, etc).


The number of ARGs varies from command to command. In most cases the ARGs need not be supplied on the command line; any that are not supplied will be obtained by prompting. The exception to this rule are those ARGs that are enclosed in [square brackets] in the command list. The presence of these ARGs changes the way the command is carried out.


Certain basic argument types recur often and are abbreviated in the following ways.


<TYPE> ::= 'se', 'sh', 'l', or 'p' for sector, ship, land unit, or plane respectively. If "sector" is not a possibility, then 's' will likely suffice for "ship".


<CNUM/CNAME> ::= either a country number or a country name


<COMM> ::= any one, (or unambiguous abbreviation), of the list of commodities found in info Selector:


<LOAN> ::= loan number


<SECT> ::= sector coordinates in the form: x,y


<SECTS> ::= sector(s) in the form:

lox:hix,loy:hiy ?cond&cond&...

lox, hix, loy, hiy are coordinates bounding the rectangular area to be considered


cond is a condition of the form:

<VALUE><OPERATOR><VALUE>

<VALUE> is either a <COMM>, as above, a number in the range 0 to 65536, a sector designation, (m for mine, c for capital, etc), a type of unit (frigate, cavalry, etc), or a selector found in info Selector.
<OPERATOR> can be any one of:

<

less than

=

equal

>

greater than

#

not equal


Thus mob=100, ore#0, 7=guns, civ#mil, des=b are examples of legitimate conditions, (note lack of embedded spaces), and
[##:##] Command : census -3:3,-3:3 ?des=+&gun=5&mil>civ

will list all highways within 3 of your capital with exactly 5 guns and more military than civilians. Similarly,
[##:##] Command : deliver f -9:9,-9:9 ?f_del=0

will allow you to set up food delivery in all the sectors that don't already have food delivery. Note that hix, hiy, and ?cond are all optional. Also, the entire lox:hix,loy:hiy section may be replaced by either #, #0, #1, #2, or #3, ... which refer to realms which you can define. (See info realm.) Note that # and #0 are equivalent. Also * refers to all sectors, and @x,y:dist refers to all sectors within dist of x,y.


<SHIP> ::= one ship number


<FLEET> ::= fleet designation, which may be a list of ships separated by slashes (`/'), a fleet letter, the character tilde (`~') which means all ships not in a specific fleet, or a rectangular sector area.


<SHIP/FLEET> ::= either a single ship number or a fleet designation. Note that <FLEET> specifications may have an optional ?cond&cond... argument like that used for <SECTS> arguments. For instance:
[##:##] Command : ship ~ ?des=d&mil>5

will list all destroyers that have more than 5 military which are not currently in any fleet.


The output from commands may also be sent to a file or another process by utilizing these alternate syntaxes:



[##:##] Command : VERB ARG1 ... > FILE

which sends the output to the file FILE.



[##:##] Command : VERB ARG1 ... >> FILE

which appends the output to the file FILE.



[##:##] Command : VERB ARG1 ... >! FILE

which sends the output to the file FILE, replacing the file it if it already exists.



[##:##] Command : VERB ARG ... | PROGRAM [ARGS...]

which send the output of the command to the program PROGRAM with optional arguments ARGS. This is most useful when PROGRAM is some type of pager like more(1) or less(1).


The Empire shell also recognizes a few control characters:


\*(fIname\*(fP

\*(fImeaning\*(fP

interrupt

Abort command and return to Empire command level

quit

Exit Empire

EOT

Exit Empire


See also : realm , Moving , Selector , Playing