What is /usr/bin/[ ?

Posted by Josh on Server Fault See other posts from Server Fault or by Josh
Published on 2010-05-05T19:04:31Z Indexed on 2010/05/05 19:08 UTC
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I was just poking around in /usr/bin and I found an ELF binary file called [. /usr/bin/[. I have never heard of this file and my first thought was that it was a clever way of hiding a program, possibly a trojan. However it's present on all my CentOS servers and seems to have no manual entry. I can hazard a guess as to what it is but I was looking for a more authoritative answer...

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