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WASI
sock_recv

sock_recv()

Receive a message from a socket.

Description

The sock_recv() function is used to receive a message from a socket. It is similar to the recv function in POSIX, but it also supports reading the data into multiple buffers in the manner of readv.

The function receives data from the socket and stores it in the provided scatter/gather vectors. The number of bytes stored in ri_data and the message flags are returned.

Syntax

  ;;; the data into multiple buffers in the manner of `readv`.
  ;;; Note: This is similar to `recv` in POSIX, though it also supports reading
  ;;; Receive a message from a socket.
  (@interface func (export "sock_recv")
    (param $fd $fd)
    ;;; List of scatter/gather vectors to which to store data.
    (param $ri_data $iovec_array)
    ;;; Message flags.
    (param $ri_flags $riflags)
    ;;; Number of bytes stored in ri_data and message flags.
    (result $error (expected (tuple $size $roflags) (error $errno)))
  )

Parameters

  • ctx: A mutable reference to the function environment.
  • sock: The file descriptor of the socket to receive from.
  • ri_data: A list of scatter/gather vectors to which the received data will be stored.
  • ri_data_len: The length of the scatter/gather vector list.
  • ri_flags: Message flags.
  • ro_data_len: A pointer to store the number of bytes read.
  • ro_flags: A pointer to store the message flags.

Return Value

The function returns a Result containing an Errno value. If the operation is successful, Errno::Success is returned. Otherwise, an appropriate Errno value indicating the error is returned.

Notes

  • The sock_recv() function receives a message from a socket and stores it in the provided scatter/gather vectors.
  • The function supports reading the data into multiple buffers.
  • The ri_data parameter represents a list of scatter/gather vectors, where each vector contains a buffer and its length.
  • The ri_data_len parameter specifies the length of the scatter/gather vector list.
  • The received data is stored in the buffers specified by the scatter/gather vectors.
  • The number of bytes read from the socket is stored in ro_data_len.
  • The message flags are stored in ro_flags.
  • The specific behavior of the sock_recv() function may vary depending on the runtime environment and underlying networking implementation.