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2:10 AM
      'DDE:' ⎕SVO 'X'
SYNTAX ERROR
      'DDE:'⎕SVO'X'
            ∧
What am I doing wrong here? ⍨
Oh. ⎕SV* are only available on Windows?
Ah, okay. So Dyalog shared variables are backed by the Windows-specific IPC mechanism, Dynamic Data Exchange (DDE), hence the limitation.
 
9 hours later…
11:45 AM
@B.Wilson I think they technically are "available" but have no valid domain, which Dyalog has a tendency to call a "syntax" error, e.g. (1∘1)42

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