From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on starla X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 Received: from nue.mailmanlists.eu (nue.mailmanlists.eu [IPv6:2a01:4f8:1c0c:6b10::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 5A4BE1F405 for ; Fri, 26 Jan 2024 05:19:31 +0000 (UTC) Authentication-Results: dcvr.yhbt.net; dkim=pass (1024-bit key; secure) header.d=ml.ruby-lang.org header.i=@ml.ruby-lang.org header.a=rsa-sha256 header.s=mail header.b=SW0s2SwF; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ruby-lang.org header.i=@ruby-lang.org header.a=rsa-sha256 header.s=s1 header.b=g7iLR//v; dkim-atps=neutral Received: from nue.mailmanlists.eu (localhost [127.0.0.1]) by nue.mailmanlists.eu (Postfix) with ESMTP id C77B781F4C; Fri, 26 Jan 2024 05:19:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ml.ruby-lang.org; s=mail; t=1706246363; bh=6RfsX3GMHv5y5dijagaO9po4MfsRK9Xw8mpGs1ZiCRY=; h=Date:References:To:Reply-To:Subject:List-Id:List-Archive: List-Help:List-Owner:List-Post:List-Subscribe:List-Unsubscribe: From:Cc:From; b=SW0s2SwFQ2HUuFUBMuqqUla6cpTb3FHczmMFMH9ph4+Xgd7iU15+Lbxiz3GCBFDdB MwXpNkA3DwrsMm5Da20nZEK19rjr1VP5iDT5ojKhHxGO6+W5LU6x9z+pq5GAAdz1Fb adDn4r+IK9Xvdi/vkLB/NoOp7pOpjMLFubLBU33I= Received: from csnrwnwx.outbound-mail.sendgrid.net (csnrwnwx.outbound-mail.sendgrid.net [198.37.146.154]) by nue.mailmanlists.eu (Postfix) with ESMTPS id 4394681EF7 for ; Fri, 26 Jan 2024 05:19:19 +0000 (UTC) Authentication-Results: nue.mailmanlists.eu; dkim=pass (2048-bit key; unprotected) header.d=ruby-lang.org header.i=@ruby-lang.org header.a=rsa-sha256 header.s=s1 header.b=g7iLR//v; dkim-atps=neutral DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ruby-lang.org; h=from:references:subject:mime-version:content-type: content-transfer-encoding:list-id:to:cc:content-type:from:subject:to; s=s1; bh=agfdbeFTP3R/ypMQjarVsnUJmhsfq9f0X93qJmpedWY=; b=g7iLR//vC3rw4w3/NnrOhUB+AabTCvqCBy3VDZAzxZFMyBMQJ5MFCRdIT/VnNyzvNEG1 ZK/gMYY3b3UaO8PtiAoEqQt5f4WvjwVPRxXARjsUG+DHeedJWAqzOTdm3REjdhQjrBNfY3 8aBkInJSnltHLnCzVu+wAYfWmVcIS3l5IwE5QDQ/ZkJecfhosIxbTEj+17mNvrweeBfPQO yIeMD9AvtGl7jrjsSmQD1gI6BB/sEB2a/CgujEzxfakRZkSbQvMMu2HmlxhrAfUUjloCZX Dgl9wnrh64xYNMdyJbqN2O6YIT1XuhFj2XwDgEjLG0bxuwlrafx4l1QeUGbMY/4g== Received: by filterdrecv-5bbdbb56cd-52lf9 with SMTP id filterdrecv-5bbdbb56cd-52lf9-1-65B340D5-5 2024-01-26 05:19:17.133211831 +0000 UTC m=+1267310.257876779 Received: from herokuapp.com (unknown) by geopod-ismtpd-28 (SG) with ESMTP id lWd9x4qvSRWtgdWGnr-qGA for ; Fri, 26 Jan 2024 05:19:17.115 +0000 (UTC) Date: Fri, 26 Jan 2024 05:19:17 +0000 (UTC) Message-ID: References: Mime-Version: 1.0 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Feature X-Redmine-Issue-Id: 20215 X-Redmine-Issue-Author: ioquatix X-Redmine-Sender: ioquatix X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-Redmine-MailingListIntegration-Message-Ids: 93013 X-SG-EID: =?us-ascii?Q?RXGrw3WrKfUduNFRrzMMcXYHKEABJI9T84jNjq2g6rBTg=2FXhHIicnPoJUXLutJ?= =?us-ascii?Q?tdNFg7BiEDMUtMCwjaLtb0ItKeRyv3NlZm6AYiJ?= =?us-ascii?Q?s0JX4OpybdHwzeEOxyXfLEGPquG2tAdfvcWyH9m?= =?us-ascii?Q?XW3UUBgL59aahvk9RADDpH23wEp4hFRHkPbGvzE?= =?us-ascii?Q?ZVnp9PjWnlTGSIsccjQRFmGQ0es=2FNFQ5pfA6loM?= =?us-ascii?Q?Y1QmcRh+B+oqWY8XgyhR6KW6S6avS6Hj228szkK?= =?us-ascii?Q?b+9Y0SSjYxxTSEXLyQOog=3D=3D?= To: ruby-core@ml.ruby-lang.org X-Entity-ID: b/2+PoftWZ6GuOu3b0IycA== Message-ID-Hash: L7XDBMX3KRAREUP4KKZNKAFR5AUMFMHO X-Message-ID-Hash: L7XDBMX3KRAREUP4KKZNKAFR5AUMFMHO X-MailFrom: bounces+313651-b711-ruby-core=ml.ruby-lang.org@em5188.ruby-lang.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.3 Precedence: list Reply-To: Ruby developers Subject: [ruby-core:116456] [Ruby master Feature#20215] Introduce `IO#readable?` List-Id: Ruby developers Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: From: "ioquatix (Samuel Williams) via ruby-core" Cc: "ioquatix (Samuel Williams)" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Issue #20215 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #20215: Introduce `IO#readable?` https://bugs.ruby-lang.org/issues/20215 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- There are some cases where, as an optimisation, it's useful to know whether more data is potentially available. We already have `IO#eof?` but the problem with using `IO#eof?` is that it can block indefinitely for sockets. Therefore, code which uses `IO#eof?` to determine if there is potentially more data, may hang. ```ruby def make_request(path = "/") client = connect_remote_host # HTTP/1.0 request: client.write("GET #{path} HTTP/1.0\r\n\r\n") # Read response client.gets("\r\n") # => "HTTP/1.0 200 OK\r\n" # Assuming connection close, there are two things the server can do: # 1. peer.close # 2. peer.write(...); peer.close if client.eof? # <--- Can hang here! puts "Connection closed" # Avoid yielding as we know there definitely won't be any data. else puts "Connection open, data may be available..." # There might be data available, so yield. yield(client) end ensure client&.close end make_request do |client| puts client.read # <--- Prefer to wait here. end ``` The proposed `IO#readable?` is similar to `IO#eof?` but rather than blocking, would simply return false. The expectation is the user will subsequently call `read` which may then wait. The proposed implementation would look something like this: ```ruby class IO def readable? !!self.closed? end end class BasicSocket # Is it likely that the socket is still connected? # May return false positive, but won't return false negative. def readable? return false unless super # If we can wait for the socket to become readable, we know that the socket may still be open. result = self.recv_nonblock(1, MSG_PEEK, exception: false) # No data was available - newer Ruby can return nil instead of empty string: return false if result.nil? # Either there was some data available, or we can wait to see if there is data avaialble. return !result.empty? || result == :wait_readable rescue Errno::ECONNRESET # This might be thrown by recv_nonblock. return false end end ``` For `IO` itself, when there is buffered data, `readable?` would also return true immediately, similar to `eof?`. This is not shown in the above implementation as I'm not sure if there is any Ruby method which exposes "there is buffered data". -- https://bugs.ruby-lang.org/ ______________________________________________ ruby-core mailing list -- ruby-core@ml.ruby-lang.org To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org ruby-core info -- https://ml.ruby-lang.org/mailman3/postorius/lists/ruby-core.ml.ruby-lang.org/