nadvsh - New adventure shell
. nadvsh [ -noplay ] [ -safe | -nosafe ]
[ -strict | -semistrict | -nostrict ]
nadvsh is the new adventure shell. It is a shell extension that makes
your shell environment act like a text adventure game. It features objects
which you may take with you in your backpack, and which you may use;
interaction with other users; and non-player characters (NPC`s), which
may either be helpful or a nuisance. Theme files may be loaded in order
to set up a specific environment with matching objects and NPC`s.
The -strict, -semistrict and -nosafe options make the shell
behave as if a corresponding play [semi]strict or play nosafe
command had been given. nostrict and safe are the defaults (see
below under COMMANDS).
The -noplay option causes the shell to read all the required
definitions, but to not engage in playing yet.
In the following commands, location denotes a valid directory.
The commands north, down etc. are intended for dedicated adventure directory hierarchies.
open: go+rwX
unlock: go+rX
close: go-w
lock: go-rwx
where X is a conditional x. Like in real life, lock implies close, open implies unlock, and a location may be unlocked and closed at the same time.
Identical to southwest.
Note that if an object name is required, and the object name contains spaces, the spaces (or the entire object name) should be quoted.
Allowed object classes are: weapon, 'missile weapon', missile, armor, helmet, shield, clothing, backpack, food, drink, or object for an ordinary item (for which the name should be specified). For user-friendliness, the object class name sword is also supported, as well as the use of a miscellaneous object name instead of object. The use of sword is discouraged.
Examples using object class:
buy 'missile weapon'
buy armor for 60
buy food as 'emmenthaler cheese'
buy drink as 'some milk' for 2
buy weapon as 'orc slayer' for 40
buy object as 'handpainted teapot'
Examples using object names:
buy sword as 'dragon killer' for 30
buy 'handpainted teapot'
Note the difference between:
drop '10 florins'
which will drop an object (probably a money object), and:
drop 10 florins
which will drop some of your money in the form of a money object.
Also, if you somehow get stuck with a money object in your inventory, you may cash it in with the sell command.
Example:
emote sighs.
This produces on the terminals of the users who are present in the same location:
Message from rene@ilturin on pts/3 at 10:23 ...
Rene Uittenbogaard sighs.
EOF
wall(1)) a message to all users currently logged in.
write(1) a message to another user.
colors . `tput smul`
Note that in the Korn shell, escape codes in the prompt string would mess up the command line being edited; therefore, prompt coloring is never used in ksh.
If the singular form of the currency is not identical to the plural form with the final 's' removed, the singular form may be specified as an optional second argument. Example: currency markoi marko
It is also allowed to specify the plural and singular forms in one argument, separated by a slash. Example: currency markoi/marko
Without arguments, the command will print the current currency unit. See also ENVIRONMENT below.
perl(1) and Date::Tolkien::Shire have
been installed (available on CPAN). See also cal.
The semistrict option will disallow any cd to a directory with a slash / in the name. The strict option will additionally disallow any cd to the parent directory. In this way, a pre-setup directory tree can be turned into a closed world. Symbolic links to directories may be used to create exits from locations with no subdirectories. Additionally, strict will prevent the current working directory from being shown in the prompt string (PS1), when there is a description present. nostrict will impose none of these restrictions.
The nosafe option will allow evaluation of commands specified in a local .nadvsh file (see below under FILES). This could be a security problem, therefore, the default is safe.
nadvsh
to be in the user`s PATH. See also play for the use of the strict
options.
When nadvsh starts up, a default (builtin) theme is loaded. This
theme may be overruled by a theme file indicated by the environment
variable NADVSH_THEME.
Non-player characters may act in ways that are not dependent on your actions. They will, however, not drop objects when you are not around, to prevent filesystem pollution; and they will not take objects from directories, to prevent non-object files being picked up by mistake.
less(1)
for Linux systems or more(1) for Unix systems.
nadvsh tries to figure out if color is
supported. You may override this check and force or suppress the use
of color.
Valid values are: nocolor to suppress color, or a colorname or escape sequence as specified under the colors command (see above).
The directory $HOME/.nadvbackpack/ is the implementation of your backpack. You may choose to set the mode to very permissive, in order to allow other users to put things in your backpack or steal from you. This is, however, not recommended if you plan to take non-adventure files in your backpack.
The directory $HOME/.nadvwield/ is the implementation of the collection of weapons you are wielding, armor, clothes and rings you are wearing, and the wands and lightsource you are wielding.
Non-player characters have their home in /var/tmp/nadvsh (or /var/nadvsh, if set up by the super-user). Their backpacks are found in subdirectories below there, e.g. /var/tmp/nadvsh/edrion/.nadvbackpack.
In any directory, a file .nadvsh may be created with a description of the location. These files are parsed line-by-line. There are several line types, each of which starts with a specific marker:
+ underwater + dark
surfacedeep + darkbynight (e.g. outdoors)
surfaceshallow + obscured (e.g. misty or raining)
nogravity hot
+ noair cold
foulair + radiation
Restriction: flags that concern vision, like dark, darkbynight and obscured should be placed before the description of the location, because the description is displayed while the file is parsed.
e: lines may be a security problem. Therefore, they are evaluated only if the following criteria are met:
^$HOME($|/) )
If the file and directory permissions and ownership are correct, but the script is running in safe mode or the directory is not included in d_mode_safe_dirs, the string (..) will be appended to the location description, to indicate that additional information was available.
In the following examples, the text in the e: and r: lines is supposed to occupy only one line.
Example 1
d:You are in a laboratory with many erlenmeyer flasks,
d:round-bottom flasks and a destillation apparatus.
p:a laboratory
e:test $(($RANDOM % 2)) -eq 0 && d_wrap_noeol "A whisp of
smoke rises from a nearby beaker."
Example 2
d:You are on the bridge. There is a large holographic
d:projection screen on one wall, depicting the asteroid
d:belt outside.
e:test -z "$d_captain_awake" &&
d_wrap_noeol "The captain has fallen asleep near
the communications panel and snores quietly."
h:You are on
p:the bridge
f:nogravity
r:if [ -z "$d_captain_awake" -a $(($RANDOM % 4)) -eq 0 ];
then d_captain_awake=1; d_wrap "The captain wakes up."; fi
Object files are plain text files containing a description of the object. They also must be marked as being an object, which means they should contain at least one line starting with an object class marker. These markers consist of an alphabetic character, an alphanumeric character, and a colon.
The description that follows the colon MUST immediately start with an alphanumeric character. This restriction was imposed to minimize the chance of finding a 'false positive' when checking a file (e.g. a tar file) on its object status. For the same reason, and for performance reasons, there is a maximum size to an object file, currently 2000 bytes.
In any description, the character sequence {pcurrency} may be used instead
of a specific currency name. This currency marker will be replaced by
the favorite currency of the player, when he/she examines it. Likewise,
{scurrency} will be replaced by the singular form of the currency.
Furthermore, objects that are charged (wands a.o.) may contain the character
sequence {chargecount} in the description, which will be replaced with
the chargecount (in English).
Example 3
fo:It is a crust of bread, and it looks quite wholesome.
The crust is of class fo (food). The marker makes the object edible for the 'eat' command.
Example 4
w1:The dagger is made of polished steel and
has a dark leather hilt.
The dagger is a class w1 object, in this case, a weapon with attack value +1. The example also shows a line which does not begin with a marker.
Example 5
a1:This is a strong, but yet light metal helmet,
c1:in the colors of the duke of Forstinea.
This item is armor which has +1 defensive value (a1 = class 'armor/+1') and which should be worn as a helmet (c0 = class 'clothing/helmet'). All armor objects should have an armor marker and a clothing marker. See the clothing types in the table below.
Example 6
mo:12 {pcurrency}.
This is a money object, representing 12 currency units. This example
demonstrates the use of {pcurrency}.
Example (wrong)
ri:An aquamarine ring radiating a soft bluish light.
li:
The problem with this object is that the class marker li (light source) is not followed with an alphanumeric character. Therefore, it does not count as a class marker. The solution is to break up the existing description across the two lines.
class description
----- -----------
w1 melee weapon (+1 strength) (dagger, knife, club)
w2 melee weapon (+2 strength) (quarterstaff, mace,
short sword, spear)
w3 melee weapon (+3 strength) (battle axe, scimitar)
w4 melee weapon (+4 strength) (polearms, long sword)
w5 melee weapon (+5 strength) (halberd, two-handed sword)
-- --
m0 firing weapon (rifle, arquebus, (laser) gun) (Not implemented)
m1 missile weapon (o1 type missile) (sling)
m2 missile weapon (o2 type missile) (light crossbow)
m3 missile weapon (o3 type missile) (heavy crossbow)
m4 missile weapon (o4 type missile) (short bow)
m5 missile weapon (o5 type missile) (long bow)
-- --
o0 missile weapon (+1 strength) (dart, knife)
o1 missile (+1 strength) (bullet)
o2 missile (+2 strength) (light quarrel)
o3 missile (+3 strength) (heavy quarrel)
o4 missile (+4 strength) (flight arrow)
o5 missile (+5 strength) (sheaf arrow)
class description ----- ----------- a1 armor (+1 defense) (helmet, gauntlets, small shield) a2 armor (+2 defense) (padded or studded leather, large shield) a3 armor (+3 defense) (scale mail, ring mail) a4 armor (+4 defense) (chain mail) a5 armor (+5 defense) (banded mail) a6 armor (+6 defense) (field plate armor)
class description
----- -----------
c1 clothing or armor worn on head (hat, cap, helmet)
c2 clothing worn on face (mask, glasses, goggles)
c3 clothing worn on upper body (jacket, vest, tunic)
c4 armor worn over upper body (chain mail,
bullet-proof vest)
c5 clothing worn over entire body (mantle, cape, robe)
c6 clothing or armor worn on hands (gloves, gauntlets)
c7 armor held in hands (shield)
c8 clothing worn on lower body (skirt, pants, trousers)
c9 clothing worn on feet (shoes, boots)
class description ----- ----------- v0 valuable object ( 0- 10 gp) v1 valuable object ( 10- 30 gp) (10 xp) v2 valuable object ( 30- 100 gp) (20 xp) v3 valuable object ( 100- 300 gp) (30 xp) v4 valuable object ( 300- 1000 gp) (40 xp) v5 valuable object ( 1000- 3000 gp) (50 xp) v6 valuable object ( 3000- 10000 gp) (60 xp) v7 valuable object ( 10000- 30000 gp) (70 xp) v8 valuable object ( 30000-100000 gp) (80 xp) v9 valuable object (100000+ gp) (90 xp) -- -- C# charge count (# = nr. of charges, in range 0-9) D# device (# = type, in range 0-9) R# rod (# = type, in range 0-9) S# staff (# = type, in range 0-9) W# wand (# = type, in range 0-9) p# potion (# = type, in range 0-9) r# magical ring (# = type, in range 0-9) s# scroll (# = type, in range 0-9)
class description ----- ----------- ba backpack dr drink fo food li light source mo money mu musical instrument ri non-magical ring sc scuba gear te teleporter -- -- ob ordinary portable object nh ordinary non-portable object (too heavy to carry) nf ordinary non-portable object (fixed to wall, floor, ...)
Other object classes are under development.
Theme files may contain descriptions of locations, objects and non-player characters. Theme files do not contain information about the whereabouts of objects. For specifications of object and location descriptions, see the descriptions under the respective headings in this man page. Theme files are read in by the theme command.
Records in a theme file may (and usually will) occupy multiple lines, and start with a line indicating the record type. There is no record separator: records start at a line beginning with the record marker. The following types of records exist:
Also, when a location description file (.nadvsh) is read in as a theme file, an loc: line is implicitly created, and the file is read in as if it were part of a theme file.
Indicated by a single lowercase letter: male, female, neuter, plural, or singular (if the gender is unknown; not recommended). The gender specification may also be used to indicate whether the NPC is considered a 'monster', by adding an o to the gender string, e.g. mo for an orc or fo for a harpy. Monsters do not talk and they don`t have backpacks.
Normally in the range 1-10, except for extreme monsters such as dragons a.o.
Charm determines how inclined the NPC is to obey your requests. Normally in the range 1-10. (Not implemented)
This determines a.o. how apt the NPC is at stealing. Normally in the range 1-10.
Following the npc: data line, there may be (multiple) lines containing a description of the character.
Example 7
loc:/home/rene/newadventure/curve
f:darkbynight
d:The road curves to the east here.
d:Cows graze calmly as you walk by.
h:You have come to
p:a curve in the road
e:if [ $d_pc_strength -lt 5 ]; then d_wrap_noeol "The mere
sight of the cows brings comfort to your heart.";
let d_pc_strength+=1; fi
obj:tungsten wand
W3:This is a tungsten wand
h3:with {chargecount} rubies
inlaid in the shaft.
npc:bobo 'Bobo Rockbiter' /home/rene/bobo m 6 8 10
Bobo is quite tall, even for a Fallohide, and has red curly hair.
npc:droid droid /usr/lib n 20 0 0
The droid does not react to your presence at all, and
continues performing system checks.
Portability is probably not optimal. Not all Un*xes have been tested.
Two nadvsh shells run by the same user are not independent. In
particular, they share the backpack directories for the user and NPC`s.
Two nadvsh shells run by different users are not independent either:
they share the NPC`s backpack directories.
The script makes a number of ``sanity assumptions'', and therefore it does not try to modify e.g. PATH, HOME, or the current nounset mode (set -u).
There are plenty opportunities for cheating. This, however, cannot be avoided in an implementation such as this.
The default theme does not provide a consistent adventure (the objects and location descriptions are from a different ``setting'' (medieval vs. contemporary)). This will be fixed later.
nadvsh has been tested on:
bash-2.05.0 (2)-release segfaults when sourcing the script.
This seems to be caused by large multiline string constants.
This manual pertains to nadvsh version 1.85.2 .
The manual pages for ksh(1), bash(1) and zsh(1).
Written by René Uittenbogaard (feedback, comments, bug reports to: ruittenb@users.sourceforge.net). Location descriptions were taken from the mud-shell (see below), with kind permission from the author, Dean Swift.
nadvsh was inspired by the following original 'adventure' shells:
This program is free software; you can redistribute it and/or modify it under the terms described by the GNU General Public License version 2.
nadvsh is distributed without any warranty, even without the implied
warranties of merchantability or fitness for a particular purpose.