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- ReadMe file about Exec ports.
-
- This little archive contains two sources (and exectuables): WaitPort.s and
- PutMsg.s. I hope they'll help you to understand ports communication in Exec
- library. Before running WaitPort, open two consoles (CLI or Shell). In one of
- them run WaitPort. Well, nothing interesting will happen, but prompt will not
- return, and it'll be looking, like WaitPort is still running. Then in other
- console run PutMsg program. You can also put some text as parameter, e.g.:
-
- 1> PutMsg It's some stupid text...
-
- and press <Return>. Now look, what will happend in the first console - the text
- you have just typed, shows in the another window! After this prompt will return
- in both consoles, and you can use them for anything else (e.g. closing... 8).
-
- The question is - what does it have in common with exec ports? Here's an
- explanation.
- First source (WaitPort.s) creates new port called "Amsterdam" and adds it to
- the system public ports list. Then it waits for message(s) that will come to
- this port. And if you run now PutMsg, it will look for public port called
- exactly "Amsterdam". If it find it, then a message will be send to that port.
- The message contains ID header (it's string "CRMX", but it can be anything
- else), length of parameter string (it's 1 (one) if there's no parameters; this
- "one" is for CR code $0a), and pointer to parameter string. WaitPort will
- receive the message, reads the parameter, writes it on the console and send
- reply message to PutMsg task. After this, both programs will quit. Now, take a
- look at the sources, to make everything clear. In case of any problems, you can
- write to me (I prefer EMail).
-
- - Cromax
-
- EMail: kita@sun10.ci.pwr.wroc.pl
- (c) 1994 by Tomislaw "Cromax" Kitynski
-