Path: utzoo!utgpu!watmath!clyde!att!rutgers!mit-eddie!bloom-beacon!bu-cs!rwd From: rwd@bu-cs.BU.EDU (Bob Deroy) Newsgroups: comp.unix.questions Subject: Re: ls -l Message-ID: <26419@bu-cs.BU.EDU> Date: 4 Dec 88 14:56:47 GMT References: <838@nih-csl.UUCP> <6060018@hpcupt1.HP.COM> Reply-To: rwd@bu-it.bu.edu (Bob Deroy) Followup-To: comp.unix.questions Organization: Boston University Lines: 26 In article <6060018@hpcupt1.HP.COM> steiny@hpcupt1.HP.COM (Don Steiny) writes: >/ hpcupt1:comp.unix.questions / reeder@ut-emx.UUCP (William P. Reeder) / 3:26 pm Nov 30, 1988 / >In article <838@nih-csl.UUCP>, ted@nih-csl.UUCP (ted persky) writes: >>> it seems that, even for long directory listings, the command takes a very short >>> amount of time to complete, considering all the file opening and closing I guess > >>My experience has been that ls can take a very long time to run on >>large directories. Several posters have already explained that ls >>doesn't have to open each file in the directory; > > To display the user name, it needs to map the uid to the name >in the /etc/passwd file. On systems with many users this can take >a long time. This really annoyed me, so I wrote a small program that reads a directory and hashes the passwd file. It runs a good deal faster than ls -l. It's not fancy and I use ls most of the time, but it does come in handy at times for those directories many users write to. If you would like to see the hashing code, mail me and I will send it to you. -- UUCP: ...!harvard!bu-cs!bu-it!rwd INTERNET: rwd@bu-it.bu.edu CSNET: rwd%bu-it@bu-cs BITNET: engbd3c@buacca