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SocketReadyQ[socket]

tests if there is any data immediately available to read from the specified socket.

SocketReadyQ[socket,t]

waits for up to t seconds to see if data becomes available to read.

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SocketReadyQ

SocketReadyQ[socket]

tests if there is any data immediately available to read from the specified socket.

SocketReadyQ[socket,t]

waits for up to t seconds to see if data becomes available to read.

Details

  • Sockets in SocketReadyQ[…] are specified using SocketObject[…].
  • SocketReadyQ returns immediately; unlike Read etc., it does not block waiting for data to become available.
  • For numeric values, t is interpreted as having units of seconds. A time Quantity can also be used.

Examples

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Basic Examples  (3)

Initially on connection, most websites will not send data until a request is made:

Wolfram Language code: sock = SocketConnect["exampledata.wolfram.com:80"]
Wolfram Language code: SocketReadyQ[sock]

Write a request to the socket and wait for up to 10 seconds for the server's response to arrive:

Wolfram Language code: WriteString[sock, "GET /50states.txt HTTP/1.0 "]; SocketReadyQ[sock, 10]

Close the socket:

Wolfram Language code: Close[sock]

Open a server socket and connect a client socket to it:

Wolfram Language code: server = SocketOpen[Automatic, "ZMQ"] client = SocketConnect[server]

Initially, neither of them has any data available:

Wolfram Language code: SocketReadyQ /@ {server, client}

Sending a message to the client makes the socket ready for reading:

Wolfram Language code: WriteString[server, "hello from the server"]; SocketReadyQ[client]

After reading the message, there is no more data available:

Wolfram Language code: SocketReadMessage[client]; SocketReadyQ[client]

Close the sockets:

Wolfram Language code: Close /@ {server, client}

Wait for a response using a Quantity as the second argument:

Wolfram Language code: sock = SocketConnect["wolfram.com:80"]; SocketReadyQ[sock, Quantity[10, "Seconds"]]

Close the socket:

Wolfram Language code: Close[sock]

Neat Examples  (1)

Make a simple ping time function, measuring how long it takes for an HTTP response to come back:

Wolfram Language code: simplePing[host_String, timeout_ : Quantity[10, "Seconds"]] := Block[{sock = SocketConnect[host], res}, WriteString[sock, "HEAD /index.html HTTP/1.1 Host: " <> host <> " "]; res = Quantity[First@AbsoluteTiming[SocketReadyQ[sock, timeout]], "Seconds"]; Close[sock]; res]

Ping a host to see how long before it responds:

Wolfram Language code: simplePing["wolfram.com:80"]

Request the page multiple times:

Wolfram Language code: Table[simplePing["wolfram.com:80"], 5]
Wolfram Research (2017), SocketReadyQ, Wolfram Language function, https://reference.wolfram.com/language/ref/SocketReadyQ.html.

Text

Wolfram Research (2017), SocketReadyQ, Wolfram Language function, https://reference.wolfram.com/language/ref/SocketReadyQ.html.

CMS

Wolfram Language. 2017. "SocketReadyQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/SocketReadyQ.html.

APA

Wolfram Language. (2017). SocketReadyQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/SocketReadyQ.html

BibTeX

@misc{reference.wolfram_2026_socketreadyq, author="Wolfram Research", title="{SocketReadyQ}", year="2017", howpublished="\url{https://reference.wolfram.com/language/ref/SocketReadyQ.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_socketreadyq, organization={Wolfram Research}, title={SocketReadyQ}, year={2017}, url={https://reference.wolfram.com/language/ref/SocketReadyQ.html}, note=[Accessed: 12-June-2026]}