Path: csiph.com!goblin1!goblin.stu.neva.ru!usenet.stanford.edu!not-for-mail From: Chet Ramey Newsgroups: gnu.bash.bug Subject: Re: Should [[ -v 1 ]] be supported? Date: Fri, 28 Dec 2018 18:23:57 -0600 Organization: ITS, Case Western Reserve University Lines: 16 Approved: bug-bash@gnu.org Message-ID: References: <5dac2cf2-2fac-0fd1-058f-6a84a3271738@case.edu> <20181228013623.mersdxbzy64dpldp@crack.deadbeast.net> <20181228015710.tzzbejk36fsgr5wb@crack.deadbeast.net> Reply-To: chet.ramey@case.edu NNTP-Posting-Host: lists.gnu.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Trace: usenet.stanford.edu 1546043049 26518 208.118.235.17 (29 Dec 2018 00:24:09 GMT) X-Complaints-To: action@cs.stanford.edu Cc: chet.ramey@case.edu, bug-bash To: Peng Yu , "G. 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Use a profiler. That's what they're for. > > I've already shown that $() is a major problem to slow down the speed > and I have reduced using its usage in my code and significantly > improved the performance. This isn't a major deductive leap, since command substitution forks a child and reads through a pipe. Forking is always more expensive than not. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/