View source for The basics of interacting with Unix

* You absolutely need the package <code>OSProcess</code>
* To get a reference to the process which is running your Cuis image do:
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UnixProcess thisOSProcess . "=> a UnixProcess with pid 14751 "
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* Then watch these interactions it should be all clear to you
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". get the current working directory of the shell when it run Cuis " 
UnixProcess thisOSProcess getCwd. "=> '/home/p/prog/cuis-project' " 

". get the pid of the Cuis process and his father pid " 
UnixProcess thisOSProcess pid.    "=> 14751 " 
UnixProcess thisOSProcess ppid.   "=> 14750 " 

" ------------ 
from here on there are class method shortcuts that let you type less but the idea is alwys the same you are asking 'UnixProcess thisOSProcess' to give you info. 
------------ " 

". get the environment variables of the shell who run Cuis " 
UnixProcess env.          "=> a Dictionary(#CLUTTER_IM_MODULE->'ibus' #COLORFGBG->'0;15' #COLORTERM->'truecolor' #DBUS_SESSION_BUS_ADDRESS->'unix:path=/run/user/1000/bus' .... #DESKTOP_SESSION->'plasma' #DISPLAY->':0.0' ) " 

". the program name corresponding to Cuis, which is the name of the OpenSmalltalkVM" 
UnixProcess programName . "=> './sqcogspur64linuxht/lib/squeak/5.0-202003021730/squeak' " 

" . the VM arguments, where there is Cuis image file and some extra parameters " 
UnixProcess arguments .   "=> #('Cuis-Smalltalk-Dev/Cuis5.0-4975.image' '-d' 'Preferences veryBigFonts.') " 

". get stdin, stdout, stderr " 
". observe that by default, as of now, stdout and stderr are both copied to Transcript but only stderr will go printed into the shell which runs Cuis. " 
UnixProcess stdOut nextPutAll: 'Hello world ! '. 
UnixProcess stdErr nextPutAll: 'Hello world ! '.

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