Program/StdOut
The Program Object represents the currently running app. This object offers functionality to execute system commands, include sub programs, read arguments and more. All system related functions.
StdOut
Out is the standard output object. It basically has two methods: write: and stop. The write: message is used to send a string to stdout, the stop message prints a newline character. Instead of stop you can also use \n.
Example:
Out write: ['Hello World'], stop.
result:
Hello World
Modules/Plugins
The world of Xoscript can be expanded with new system objects, by installing modules . A new system object can be added to the world of Xoscript by placing the module file (usually a file with the suffix .so or .dll) into the mods folder.
When you send a message to the object that is made available through the plugin module, it will be automatically loaded by Xoscript.
Reflection
There are various ways for system exploring during program execution. Xoscript holds a couple of methods to detect which objects are present and to which messages these objects respond. Firstly, each object can be asked what type it is, however types in Xoscript are malleable and therefore unreliable.
It is also possible to ask the Program object if a given object is already present in the program:
Program Tool true: { ... }.
In case of an object name which consists of one single symbol, it is best to apply the following notation to avoid confusion:
Program find: ['X'], true: { ... }.
Besides asking about objects, it is equally possible to ask the Program object about messages. For instance, it can be asked if the object Number knows the message between:and:, in the way as is illustrated below:
Program Number: ['between:and:'], stop.
[ Program ] memory: [Number]
Example:
Program memory: 8 MB.
Program memory: 500 KB.
Result:
automatically generated from test: #550
[ Program ] memory-management: [ Number ]
Example:
# Available GC Modes:
# 0 - Disabled
# 1 - Active (default)
# 4 - Collect every cycle (testing only)
# 8 - Reserved (not in use)
# In theory modes can be combined (n/a now)
# Disable GC
Program memory-management: 0.
# request GC mode setting to confirm
Out write: Program gcmode, stop.
Result:
automatically generated from test: #736
[ Program ] gcmode
Example:
# Available GC Modes:
# 0 - Disabled
# 1 - Active (default)
# 4 - Collect every cycle (testing only)
# 8 - Reserved (not in use)
# In theory modes can be combined (n/a now)
# Disable GC
Program memory-management: 0.
# request GC mode setting to confirm
Out write: Program gcmode, stop.
Result:
automatically generated from test: #736
[ Program ] shell-escape: [ String ]
Example:
# Program shell-escape produces canonical posix shell syntax
# compatible with: bash/dash, zsh, ksh
>> c := Program shell-escape: ['abc'].
Out write: c, stop.
Out write: ( Program os: ['echo '] + c ), stop.
c := Program shell-escape: ['a'b'c'].
Out write: c, stop.
Out write: ( Program os: ['echo '] + c ), stop.
c := Program shell-escape: ['a\'c'].
Out write: c, stop.
Out write: ( Program os: ['echo '] + c ), stop.
Result:
automatically generated from test: #634
[ Program ] os: [ String ]
Example:
#Linux
>> x := Program os: Command uname.
Out write: x.
Result:
automatically generated from test: #551
[ Program ] chdir: [ String ]
Example:
Program chdir: ['/tmp'].
Out write: (Program os: Command pwd).
Result:
automatically generated from test: #680
[ Program ] mkdir: [ String ] mode: [ Number ]
Example:
#Linux
Server init.
Program mkdir: ['/tmp/b'] mode: Oct o777.
Out write: (Program os: ['stat -c"%a" /tmp/b']) trim, stop.
Program os: ['rmdir /tmp/b'].
Result:
automatically generated from test: #681
[ Program ] argument: [ Number ]
Example:
>> x := Program argument: 1.
Out write: x, stop.
Result:
automatically generated from test: #552
[ Program ] number.
Example:
>> x := Program number.
Out write: x, stop.
Result:
automatically generated from test: #553
[ Program ] string
Example:
>> x := Program string.
Out write: x, stop.
Result:
automatically generated from test: #554
[ Program ] path
Example:
>> path := Program path.
(path contains: ['/bin']) true: {
Out write: ['OK'], stop.
}.
Result:
automatically generated from test: #654
[ Program ] use: [ String ]
Example:
>> f := File new: (Path /tmp: ['x.ctr']).
f write: ['>> x := 123.'].
Program use: (Path /tmp: ['x.ctr']).
Out write: x, stop.
Result:
automatically generated from test: #555
[ Program ] [ String ]
Example:
Out write: Program Object, stop.
Out write: Program Dream, stop.
Result:
automatically generated from test: #556
[ Program ] find: [ String ]
Example:
Out write: (Program find: ['✎']), stop.
Out write: (Program find: ['Q']), stop.
Result:
automatically generated from test: #557
[ Program ] [ String ]: [ String ]
Example:
Out write: (Program ✎: ['AAA']), stop.
Out write: (Program Program: ['test']), stop.
Result:
automatically generated from test: #558
[ Program ] arguments
Example:
Out write: Program arguments, stop.
Result:
automatically generated from test: #559
[ Program ] end
Example:
Out write: ['1..2..3..'], stop.
Program end.
Out write: ['4..5..6..'], stop.
Result:
automatically generated from test: #560
[ Program ] alarm: [ Number ]
Example:
# Setting alarm
# terminates the program after 1 sec.
Program alarm: 1.
Out write: ['max 1 sec.'], stop.
Moment wait: 2.
Out write: ['takes too long.'], stop.
# note:
# Setting an alarm is irreversible,
# an attacker cannot disable it.
# After the first call, the alarm is locked.
# Also the alarm is really harsh,
# the program *WILL* be stopped after the
# specified time interval, even if it is
# in a blocking read or something.
# note:
# Alarm is heavy, consider setting basic
# timeouts in the webserver instead.
Result:
automatically generated from test: #637
[ Program ] pledge: [ String ]
Example:
#OBSD
# see https://man.openbsd.org/pledge for details
Program pledge: ['stdio'].
Out write: ['stdio allowed'], stop.
File list: ['/'].
Out write: ['process killed'], stop.
Result:
automatically generated from test: #643
[ Program ] unveil: [ String ] permissions: [ String ]
Example:
#OBSD
File list: ['/'].
# for details: https://man.openbsd.org/unveil
Program unveil: ['/tmp'] permissions: ['r'].
Program unveil: None permissions: None. # lock
{ File list: ['/']. } except: {
Out write: ['not unveiled!'], stop.
}, start.
Result:
automatically generated from test: #644
[ Program ] setting: [ String ]
Example:
#Linux
>> x := Program setting: ['SHELL'].
Out write: x, stop.
Program setting: ['TEST'] value: ['123'].
>> x := Program setting: ['TEST'].
Out write: x, stop.
Result:
automatically generated from test: #561
[ Program ] setting: [ String ] value: [ String ]
Example:
#Linux
>> x := Program setting: ['SHELL'].
Out write: x, stop.
Program setting: ['TEST'] value: ['123'].
>> x := Program setting: ['TEST'].
Out write: x, stop.
Result:
automatically generated from test: #562
[ Program ] ask
Example:
#Out write: Program ask, stop.
#@result
#~$ hello_
#hello
#~$_
Result:
automatically generated from test: #563
[ Program ] ask password
Example:
#Out write: Program ask-password, stop.
#@result
#~$ ****_
#1234
#~$_
Result:
automatically generated from test: #564
[ Program ] input
Example:
Server init.
>> message := ['this is a string to be encrypted!'].
>> key := ['secret123!'].
>> vault := Vault new: ['myvault'].
>> encrypted := vault encrypt: message key: key.
>> decrypted := vault decrypt: encrypted key: key.
Out
write: ['Message:'], stop
write: message, stop
write: ['Decrypted:'], stop
write: decrypted, stop.
Result:
automatically generated from test: #565
[ Program ] flush
Example:
Out write: ['Flush stdout buffer.'], stop.
Program flush.
Result:
automatically generated from test: #566
[ Program ] error: [ String ]
Example:
Program error: ['123'].
Result:
automatically generated from test: #567
[ Program ] version: [ Moment ]
Example:
# backward compatibility forever
>> now := Moment new
year: 1993,
month: 1.
# program will always remain compatible with 1993-1
Program version: now.
Out write: ['
This program
will always run
like it ran in 1993!
Even with the latest
updates.
'], stop.
Result:
automatically generated from test: #633
[ Program ] feature: [ String ] enable: [ Boolean ]
Example:
# toggle feature
>> feature := Program feature: ['RECURSIVE_STRINTPOL'].
Out write: feature, stop.
Program feature: ['RECURSIVE_STRINTPOL'] enable: True.
feature := Program feature: ['RECURSIVE_STRINTPOL'].
Out write: feature, stop.
Result:
automatically generated from test: #666
[ Program ] feature: [ String ]
Example:
# toggle feature
>> feature := Program feature: ['RECURSIVE_STRINTPOL'].
Out write: feature, stop.
Program feature: ['RECURSIVE_STRINTPOL'] enable: True.
feature := Program feature: ['RECURSIVE_STRINTPOL'].
Out write: feature, stop.
Result:
automatically generated from test: #666