Commands tagged unix (65)

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Serve current directory tree at http://$HOSTNAME:8000/

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Update IP filter for qBittorrent
Downloads Bluetack's level 1 IP blocklist in .p2p format, suitable for various Bittorrent clients.

grep for tabs without using Ctrl-V trick
-P tells grep to use perl regex matches (only works on the GNU grep as far as I know.)

Listing directory content of a directory with a lot of entries
Ever wanted to get the directory content with 'ls' or 'find' and had to wait minutes until something was printed? Perl to the rescue. The one-liner above(redirected to a file) took less than five seconds to run in a directory with more man 2 million files. One can adapt it to e.g. delete files that match a certain pattern.

backup and synchronize entire remote folder locally (curlftpfs and rsync over FTP using FUSE FS)
connect to a remote server using ftp protocol over FUSE file system, then rsync the remote folder to a local one and then unmount the remote ftp server (FUSE FS) it can be divided to 3 different commands and you should have curlftpfs and rsync installed

recurisvely md5 all files in a tree
Found this little gem here: http://info.michael-simons.eu/2008/10/25/recursively-md5sum-all-files-in-a-directory-tree/

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