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Lua

Check Whether a Socket Is Writable

See more Socket/SSL/TLS Examples

Demonstrates Socket.CheckWriteable, which waits for the connected socket to become writable. It returns 1 if writable, 0 if it did not become writable before the timeout, or -1 on error.

Background. A maxWaitMs of 0 performs a nonblocking poll. This is useful for flow control before attempting a large send.

Chilkat Lua Downloads

Lua
local chilkat = require("chilkat")

local socket = chilkat.Socket.new()

-- Connect to the server using TLS.
local bTls = true
local maxWaitMs = 5000
local success = socket:connect("example.com", 5000, bTls, maxWaitMs)
if not success then
    print(socket.last_error_text)
    return
end

-- Wait up to 5 seconds for the socket to become writable.  Returns 1 if writable, 0 if it did not
-- become writable before the timeout, or -1 on error.
local writable = socket:check_writeable(5000)
if writable < 0 then
    print(socket.last_error_text)
    return
end

if writable ~= 1 then
    print("The socket did not become writable before the timeout.")
    return
end

print("The socket is writable.")