tests whether there is an expression ready to read from the specified MathLink connection.

LinkReadyQ[link, t]
waits for up to t seconds to see if an expression becomes ready to read.

LinkReadyQ[{link1, link2, ...}, t]
tests all the in parallel, returning as soon as any of them are ready to read from.


  • The must be active LinkObject objects, as returned by functions like LinkLaunch or Links.
  • LinkReadyQ[{link1, link2, ...}, t] returns a list of True and False, specifying which of the are ready to read from.
  • If LinkReadyQ[link] returns True, then LinkRead[link] will not block under any normal circumstances.
  • If LinkReadyQ[link] returns False, then LinkRead[link] will block, and will not return until something becomes available to read on link.
  • LinkReadyQ[link] tests whether there is any data to read; it cannot determine whether the data represents a complete expression.
  • The basic form of LinkReadyQ corresponds to the MathLink library function MLReady().

ExamplesExamplesopen allclose all

Basic Examples (1)Basic Examples (1)

Launch a subsidiary Mathematica kernel process:

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Test whether there is an expression ready to be read:

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Read the expression:

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Close the link:

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