Date: Mon, 13 Nov 2000 11:35:20 -0500 From: "Andresen,Jason R." <jandrese@mitre.org> To: Tommy Forrest - KE4PYM <tforrest@mcs.net> Cc: "freebsd-questions@FreeBSD.ORG" <freebsd-questions@FreeBSD.ORG> Subject: Re: What is "["? Message-ID: <3A101848.D9F7105E@mitre.org> References: <200011130004.SAA06022@mailbox.mcs.net>
next in thread | previous in thread | raw e-mail | index | archive | help
Tommy Forrest - KE4PYM wrote: > > Rooting around (no pun intended) my 4.0 system today I happened upon > a file called "[" in /bin. Not knowing what this file was I deleted > it. > > Rule number one: Dont delete that in which you do not know. Rename > it. > > Lesson learned. Soon after my network died. I rebooted the system. > Lots of bad things (tm) happened. Nothing would start up. So I > logged in and did a man [ and found it was a test utility. Then I > did a locate test |more Found /bin/test. Copied test to [ and > rebooted. Everything is happy. > > What, exactly, is "[". Why is it on my system as "["? It's the test command, just like the manpage said. It's called "[" so people writing shell scripts can do something like if [ -e file ] do good stuff done instead of if test -e file do good stuff done It makes shell scripting a little more readable. BTW, don't copy test to "[" hard link it instead. Both files are the same, and when test is updated, you want "[" to be updated as well. Besides, right now you have a redundant copy of test sitting on your system eating disk space (in root). -- _ _ _ ___ ____ ___ ______________________________________ / \/ \ | ||_ _|| _ \|___| | Jason Andresen -- jandrese@mitre.org / /\/\ \ | | | | | |/ /|_|_ | Views expressed may not reflect those /_/ \_\|_| |_| |_|\_\|___| | of the Mitre Corporation. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3A101848.D9F7105E>