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Tue, 26 Apr 2022 00:01:16 -0700 (PDT) MIME-Version: 1.0 References: <20220425192036.p6awbyro2a2lp7bq@chazelas.org> In-Reply-To: From: Bart Schaefer Date: Tue, 26 Apr 2022 00:01:04 -0700 Message-ID: Subject: Re: ZSH performance regression in 5.8.1.2-test To: Jordan Patterson , Zsh hackers list Content-Type: multipart/mixed; boundary="0000000000004edd5105dd894221" X-Seq: 50102 Archived-At: X-Loop: zsh-workers@zsh.org Errors-To: zsh-workers-owner@zsh.org Precedence: list Precedence: bulk Sender: zsh-workers-request@zsh.org X-no-archive: yes List-Id: List-Help: List-Subscribe: List-Unsubscribe: List-Post: List-Owner: List-Archive: --0000000000004edd5105dd894221 Content-Type: text/plain; charset="UTF-8" On Mon, Apr 25, 2022 at 2:27 PM Bart Schaefer wrote: > > Theoretically we can block-read with impunity in cases 1 and 2 (anyone > disagree?). Testing for seek-ability would allow doing the "read too > much and back up" trick in case 3. I don't immediately see any way to > avoid reading one byte at a time in case 4, does anyone have a > suggestion? 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