All commands (14,187)

  • This doesn't make any assumptions about your IP address and prints out one IP address per line if you have multiple network interfaces. Show Sample Output


    -3
    ifconfig | sed '/.*addr.*Bcast.*/ ! d'| sed 's/.*addr:\([0-9\.]*\).*/\1/'
    Haegin · 2010-03-26 08:13:13 3
  • This assumes your local ip starts with 192.something (e.g. 192.168), it greps ifconfig output for an ip that starts with 192, then strips the extra garbage (besides the ip) Maybe `ifconfig | grep addr | grep Bcast` would also do it Show Sample Output


    -5
    ifconfig | grep addr:192 | sed s/Bcast.*// | sed 's/^.*inet addr://'
    hasenj · 2010-03-26 07:37:21 4
  • This is useful for examining the path. Show Sample Output


    6
    printf ${PATH//:/\\n}
    haivu · 2010-03-26 04:37:33 5
  • Okay, Jimmy, the command 'optical-monitor' is needed within the global config. for this command to work (and if supported by your licsense: yada yada, blah, blah). But, like its mad PHAT Kid, you dig? Basically, a Foundry/Brocade switch is reading the Laser light levels just like those Fiber test kits from Owl that cost 4k. I know, I also find it hard to contain myeself ;-) No really..... Show Sample Output


    -3
    show optic <slot #>
    rootgeek · 2010-03-26 03:07:22 3
  • You need all those commands, in the sample output. I had some of this, but had to play, add remove, type random stuff like a monkey to finally get this working (clearly those IP's are fake to protect the guilty, and so is the key). Show Sample Output


    -3
    aaa authentication login default local tacacs+
    rootgeek · 2010-03-26 02:58:03 3
  • This is how you make sure that ports in a VLAN remain, root ports. Typically, you would use this command on all your Core-1 switch VLAN ports, and then use 'rstp priority 1' on all your Core-2 switches. This is if you have a dual L3 core that is. Show Sample Output


    -3
    rstp priority 0
    rootgeek · 2010-03-26 02:51:54 3
  • 'no untag' is applied to _all_ ports under the default VLAN. Otherwise the default VLAN runs untagged over all physical ports. Pretty good idea to 'prune' your VLANs and define which ones pass over and across trunks that carry the default VLAN traffic. Show Sample Output


    -3
    no untag
    rootgeek · 2010-03-26 02:45:32 3
  • The sample output, is the command with a ?, to show you all the stuff you can look at. Show Sample Output


    -4
    dm ?
    rootgeek · 2010-03-26 02:42:21 3
  • The sample output, is a display of the values you can change, using this command. After a change of of these settings you will need to reload the box, by typing...wait...wait for IT: 'reload'. This comes in handy when working with the RX hardware, for example, which has a base limitation of 32 (RSTP (802-1w) instances. For all of you paying attention that means if you run RSTP on a RX you can only have 32 VLANs. Sure, you can have common groups of VLANs, like back in the day style MSTP, PVST, PVST+ (and all that old STP (802.1d) mess), before "per vlan spanning-tree", RSTP (802-1w), was made. But who wants to do all that? Show Sample Output


    -2
    system max <some value>
    rootgeek · 2010-03-26 02:39:00 5

  • -4
    sh default values
    rootgeek · 2010-03-26 02:36:57 4
  • Here "^M" is NOT "SHIFT+6" and "M". Type CTRL+V+M to get it instead. Its shortest and easy. And its sed!, which is available by default in all linux flavours.. no need to install extra tools like fromdos.


    4
    sed -i 's/^M//' file
    sata · 2010-03-25 19:34:08 7
  • This is easy to type if you are looking for a few (hundred) "missing" megabytes (and don't mind the occasional K slipping in)... A variation without false positives and also finding gigabytes (but - depending on your keyboard setup - more painful to type): du -hs *|grep -P '^(\d|,)+(M|G)'|sort -n (NOTE: you might want to replace the ',' according to your locale!) Don't forget that you can modify the globbing as needed! (e.g. '.[^\.]* *' to include hidden files and directories (w/ bash)) in its core similar to: http://www.commandlinefu.com/commands/view/706/show-sorted-list-of-files-with-sizes-more-than-1mb-in-the-current-dir Show Sample Output


    3
    du -hs *|grep M|sort -n
    tuxlifan · 2010-03-25 19:20:24 4
  • Finds all C++, Python, SWIG files in your present directory (uses "*" rather than "." to exclude invisibles) and counts how many lines are in them. Returns only the last line (the total). Show Sample Output


    2
    find * \( -name "*.[hc]pp" -or -name "*.py" -or -name "*.i" \) -print0 | xargs -0 wc -l | tail -n 1
    neologism · 2010-03-25 18:58:29 4

  • 2
    ls -d $(echo ${PATH//:/ }) > /dev/null
    ger · 2010-03-25 17:38:57 3
  • Using this command one can cut a piece from the end of an audio file.


    1
    sox input.wav output.wav reverse trim 00:00:00.3 reverse
    bodo · 2010-03-25 13:38:44 3

  • -2
    printf "%.50d" 0 | tr 0 -
    sata · 2010-03-25 12:52:45 3
  • essentially the ruby one, but perhaps has a larger installed base


    9
    python -c 'print "-"*50'
    funky · 2010-03-25 11:09:30 6
  • This feels more intuitive to me.


    1
    for i in `seq 1 1 50`; do echo -n -; done
    Gosha · 2010-03-25 10:22:19 3

  • 5
    svn log -r {`date +"%Y-%m-%d" -d "1 month ago"`}:HEAD|grep '^r[0-9]' |cut -d\| -f2|sort|uniq -c
    ivanatora · 2010-03-25 09:43:15 4
  • Get there by going backwards and forgetting the numbers.


    5
    seq -s" " -50 -1 | tr -dc -
    DoNotRememberMe · 2010-03-25 06:00:24 32
  • If you want to relocate a package on your own, or you just want to know what those PREIN/UN and POSTIN/UN scripts will do, this will dump out all that detail simply. You may want to expand the egrep out other verbose flags like CHANGELOGTEXT etc, as your needs require. It isn't clear, but the formatting around $tag is important: %{$tag} just prints out the first line, while [%{$tag }] iterates thru multi-line output, joining the lines with a space (yes, there's a space between the g and } characters. To break it out for all newlines, use [%{$tag\n}] but the output will be long. This is aside from rpm2cpio | cpio -ivd to extract the package files.


    0
    rpm --querytags | egrep -v HEADERIMMUTABLE | sort | while read tag ; do rpm -q --queryformat "$tag: [%{$tag} ]\n" -p $SomeRPMfile ; done
    DoNotRememberMe · 2010-03-25 05:40:48 3
  • The example is a little bit bogus, but applies to any command that takes a while interactively, or might be a bit of a drag on system resources. Once the command's output is saved to a variable, you can then echo "$OUTPUT" to see it in multi-line glory after that. The use of double-quotes around the backticks and during the variable expansion disables any IFS conversion during those two operations. Very useful for reporting that might pull different lines out, like from dmidecode, inq or any other disk detail command. The only caveat is that storing too much in a variable might make your shell process grow.


    0
    OUTPUT="`find / -type f`" ; echo "$OUTPUT" | grep sysrq ; echo "$OUTPUT" | grep sysctl ; echo "$OUTPUT" | less
    DoNotRememberMe · 2010-03-25 05:02:10 5
  • I had problems in Ubuntu while trying to edit /etc/resolv.conf, even with sudo I couldn't make any change. After a 2 minutes search on google I found this command. Hope someone finds it useful. It works like chmod, with + and - to denote which attributes are being added and which are being removed. See other attributes on man pages or on wikipedia http://en.wikipedia.org/wiki/Chattr


    1
    sudo chattr -i <file that cannot be modified>
    leovailati · 2010-03-25 03:14:34 4

  • 2
    aptitude search '~i!~E' | grep -v "i A" | cut -d " " -f 4
    XORwell · 2010-03-25 00:40:51 6
  • Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.


    32
    :w !sudo tee > /dev/null %
    idemal · 2010-03-24 20:04:26 13
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Check These Out

Resume a partially copied file

list block devices
Shows all block devices in a tree with descruptions of what they are.

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.

list block devices
Shows all block devices in a tree with descruptions of what they are.

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

Fill up disk space (for testing)
Put into some file. No special purpouse, just for fun...

find out how many days since given date
Exactly the same number of characters, exactly the same results, but with bc

Functions to display, save and restore $IFS
You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy. To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent. This function saves it in a variable called $saveIFS: $ sifs () { saveIFS=$IFS; } Use this function to restore it $ rifs () { IFS=$saveIFS; } Add this line in your ~/.bashrc file to save a readonly copy of $IFS: $ declare -r roIFS=$IFS Use this function to restore that one to $IFS $ rrifs () { IFS=$roIFS; }

Take a screenshot of the window the user clicks on and name the file the same as the window title
In general, this is actually not better than the "scrot -d4" command I'm listing it as an alternative to, so please don't vote it down for that. I'm adding this command because xwd (X window dumper) comes with X11, so it is already installed on your machine, whereas scrot probably is not. I've found xwd handy on boxen that I don't want to (or am not allowed to) install packages on. NOTE: The dd junk for renaming the file is completely optional. I just did that for fun and because it's interesting that xwd embeds the window title in its metadata. I probably should have just parsed the output from file(1) instead of cutting it out with dd(1), but this was more fun and less error prone. NOTE2: Many programs don't know what to do with an xwd format image file. You can convert it to something normal using NetPBM's xwdtopnm(1) or ImageMagick's convert(1). For example, this would work: "xwd | convert fd:0 foo.jpg". Of course, if you have ImageMagick already installed, you'd probably use import(1) instead of xwd. NOTE3: Xwd files can be viewed using the X Window UnDumper: "xwud <foo.xwd". ImageMagick and The GIMP can also read .xwd files. Strangely, eog(1) cannot. NOTE4: The sleep is not strictly necessary, I put it in there so that one has time to raise the window above any others before clicking on it.

follow the content of all files in a directory
The `-q' arg forces tail to not output the name of the current file


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