Commands by pooderbill (4)

  • Useful for finding newly added lines to a file, tail + can be used to show only the lines starting at some offset. A syslog scanner would look at the file for the first time, then record the end_of_file record number using wc -l. Later (hours, days), scan only at the lines that were added since the last scan. Show Sample Output


    1
    tail +### MYFILE
    pooderbill · 2015-04-23 11:49:15 0
  • view is the command: vi -r which opens a file in read-only mode. The + character jumps to the bottom of the logfile where the most relevant information starts. Other aliases can be created for commonly viewed logfiles. Show Sample Output


    -1
    view + LOGFILE
    pooderbill · 2015-04-21 11:23:01 3
  • ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line. Show Sample Output


    14
    ps -fC PROCESSNAME
    pooderbill · 2015-04-20 13:09:44 3
  • The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: noc /etc/hosts or grep server /etc/hosts | noc Change to nawk depending awk versions. Show Sample Output


    1
    alias noc="awk 'NF && ! /^[[:space:]]*#/'"
    pooderbill · 2014-09-07 00:50:57 1

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Load all files (including in subdirs), whose name matches a substring, into Vim
This command searches the current directory, and all of its subdirs, for files that have the string "foo" in their filename (foo.c, two-foo.txt, index-FOO-bar.php, etc), and opens them in Vim. It ignores any hidden .svn directories. Change -iname to -name if you want to do case-sensitive matches. Files open in buffers by default, so to verify that the correct files were opened, type ":list". You can load all the files in tabs by doing ":tab ball" or use 'vim -p' on the command-line to load files straight to tabs. If you get permission denied errors, do: vim $(find . ! -path \*.svn\* -type -f iname \*foo\* 2>/dev/null) To narrow it down to a single file extension, such as .php files, use \*foo\*.php (or '*foo*.php'. Which ever you prefer)

Get your commandlinefu points (upvotes - downvotes)
This version prints current votes and commands for a user. Pass the user as an argument. While this technically "fits" as a one liner, it really is easier to look at as a shell script with extra whitespace. :)

get xclip to own the clipboard contents
"Copying" things to the X clipboard doesn't normally create a copy. Rather the data to be 'copied' is referenced. This means that if the application that you 'copied' stuff from is closed, that data is lost. If the application that you 'copied' from is suspended with CTRL-Z, there could be some issues if you try to paste it into something. This command will create a copy of referenced data and have xclip be the provider of it, so you can then go ahead and close the app that contains the original information. Caveat: I'm not sure if this is binary-safe (though i would expect it to be), and don't know what would happen if you used it to clip a 20 meg gimp image. This technique becomes more convenient if you set it up as an action in a clipboard manager (eg klipper, parcellite). Some of these applets can take automatic action based on a variety of parameters, so you could probably just get it to always own the clipped data whenever data is clipped.

See a full list of compiler defined symbols
From http://lists.debian.org/debian-devel/2001/01/msg00971.html .

monitor network traffic and throughput in real time
see http://iptraf.seul.org/ for all kinds of documentation and screenshots

Undo mkdir -p new/directory/path
Removes all directories on given path, working from right to left, and stops when reaching a non-empty directory Counterpart of $ mkdir -p new/directory/path Shortcut (must be issues as next command immediately after mkdir): $ ^mk^rm ( see http://www.commandlinefu.com/commands/view/19/runs-previous-command-but-replacing )

Blackhole any level zones via dnsmasq
Explanation It creates dnsmasq-com-blackhole.conf file with one line to route all domains of com zones to 0.0.0.0 You might use "address=/home.lab/127.0.0.1" to point allpossiblesubdomains.home.lab to your localhost or some other IP in a cloud.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Find the package that installed a command


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