Commands by kFiddle (10)

  • The symlinks command can show status of all symbolic links, including which links are dangling, which symlinks point to files on other file systems, which symlinks use ../ more than necessary, which symlinks are messy (e.g. having too many slashes or dots), etc. Other useful things it can do include removing all dangling links (-d) and converting absolute links to relative links (-c). The path given must be an absolute path (which is why I used $(pwd) in the example command).


    6
    symlinks -r $(pwd)
    kFiddle · 2009-05-01 23:33:10 2
  • Most of you are probably familiar with the "apropos" command for searching man pages. However, did you know there's a similar command inside of gdb? If, for example, you wanted to know all gdb commands that related to threads, you could type "apropos thread". Type "help some_command" to receive more information about a command. Type "help" by itself to see a list of help topics.


    0
    gdb command: apropos <keyword>
    kFiddle · 2009-05-01 23:19:35 0
  • Sometimes "ls" is just too slow, especially if you're having problems with terminal scroll speed, or if you're a speed freak. In these situations, do an echo * in the current directory to immediately see the directory listing. Do an echo * | tr ' ' '\n' if you want a column. Do an alias ls='echo *' if you want to achieve higher echelons of speed and wonder. Note that echo * is also useful on systems that are so low in memory that "ls" itself is failing - perhaps due to a memory leak that you're trying to debug.


    -5
    echo *
    kFiddle · 2009-04-17 21:40:58 5
  • I've seen some versions of hostname that don't have the -i option, so this may not work everywhere. When available, it's a better alternative than using ifconfig and wasting eyeball muscle to search for the address, and it's definitely simpler than using awk/sed.


    -2
    hostname -i
    kFiddle · 2009-04-17 21:26:56 3
  • This is a simple command, but extremely useful. It's a quick way to search the file names in the current directory for a substring. Normally people use "ls *term*" but that requires the stars and is not case insensitive. Color (for both ls and grep) is an added bonus.


    6
    alias lg='ls --color=always | grep --color=always -i'
    kFiddle · 2009-04-11 23:15:12 3
  • Reduce the number of keystrokes it takes to open a file in vim. First of all, you just need to type "v", which is less than half the number of characters (!), and second-of-all, you only need to enter a substring of the file you want to open. For example, if you want to open the file, homework.txt, then type "v hom" to open it. Good tip is to use the lowest unique substring, otherwise you'll open multiple files in different buffers (which is sometimes desirable). Use Ctrl-^ to switch between buffers.


    0
    function v { if [ -z $1 ]; then vim; else vim *$1*; fi }
    kFiddle · 2009-04-11 23:06:43 3
  • This example, for example, produces the output, "Fri Feb 13 15:26:30 EST 2009"


    48
    date -d@1234567890
    kFiddle · 2009-04-11 22:26:41 7
  • Have a grudge against someone on your network? Do a "find -writable" in their directory and see what you can vandalize! But seriously, this is really useful to check the files in your own home directory to make sure they can't inadvertently be changed by someone else's wayward script.


    4
    find -writable
    kFiddle · 2009-04-11 22:16:35 0
  • Info has some of the worst keybindings I've ever seen. Being a vim user, I attribute that to emacs influence. Use the --vi-keys option to use some of the vi keybindings, although this won't change all the keybindings. Use the "infokey" program to have more control over info keybindings.


    8
    info --vi-keys
    kFiddle · 2009-04-11 22:10:08 4
  • Although less behaves more or less like vim in certain aspects, the vim regex for word boundaries (\< and \>) do not work in less. Instead, use \b to denote a word boundary. Therefore, if you want to search for, say, the word "exit", but do not want to search for exiting, exits, etc., then surround "exit" with \b. This is useful if you need to search for specific occurrences of a keyword or command. \b can also be used at just the beginning and end, if needed.


    5
    \bTERM\b
    kFiddle · 2009-04-11 22:05:12 1

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Save your open windows to a file so they can be opened after you restart
This will save your open windows to a file (~/.windows). To start those applications: $ cat ~/.windows | while read line; do $line &; done Should work on any EWMH/NetWM compatible X Window Manager. If you use DWM or another Window Manager not using EWMH or NetWM try this: $ xwininfo -root -children | grep '^ ' | grep -v children | grep -v '' | sed -n 's/^ *\(0x[0-9a-f]*\) .*/\1/p' | uniq | while read line; do xprop -id $line _NET_WM_PID | sed -n 's/.* = \([0-9]*\)$/\1/p'; done | uniq -u | grep -v '^$' | while read line; do ps -o cmd= $line; done > ~/.windows

Mutt - Change mail sender.

exec chmod to subfiles
Using `-exec cmd {} +` causes find to build the command using all matching filenames before execution, rather than once per file.

Outputs a 10-digit random number

Command to logout all the users in one command
It's only to logout all other user's except "root"

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

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Open (in vim) all modified files in a git repository
For editing files added to the index: $ vim `git diff --name-only --cached` To edit all changed files: $ vim `git diff --name-only HEAD` To edit changed files matching glob: $ vim `git diff --name-only -- '*.html'` If the commands needs to support filenames with whitespace, it gets a bit hacky (see http://superuser.com/questions/336016/invoking-vi-through-find-xargs-breaks-my-terminal-why for the reason): $ git diff --name-only -z | xargs -0 bash -c '

Add line number count as C-style comments
I often find the need to number enumerations and other lists when programming. With this command, create a new file called 'inputfile' with the text you want to number. Paste the contents of 'outputfile' back into your source file and fix the tabbing if necessary. You can also change this to output hex numbering by changing the "%02d" to "%02x". If you need to start at 0 replace "NR" with "NR-1". I adapted this from http://osxdaily.com/2010/05/20/easily-add-line-numbers-to-a-text-file/.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials


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