All commands (14,187)

  • show your private/local ip address

    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
  • show your private/local ip address

    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
  • Show the PATH, one directory per line

    This is useful for examining the path. Show Sample Output


    6
    printf ${PATH//:/\\n}
    haivu · 2010-03-26 04:37:33 5
  • fiber power levels on Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    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
  • tacacs+ Auth to (Cisco ACS) from Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    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
  • 802-1w (RSTP) 'root port' hard code, Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    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
  • Important 'default VLAN' command, for Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    '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
  • Dispaly a bunch of Info. on Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    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
  • Change default values on Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    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
  • Display default values on Foundry (Brocade) RX and MLX BigIron L3 (routers & switches)

    Show Sample Output


    -4
    sh default values
    rootgeek · 2010-03-26 02:36:57 4
  • Convert files from DOS line endings to UNIX line endings

    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
  • easily find megabyte eating files or directories

    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
  • Find how much of your life you've wasted coding in the current directory

    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
  • Show Directories in the PATH Which does NOT Exist


    2
    ls -d $(echo ${PATH//:/ }) > /dev/null
    ger · 2010-03-25 17:38:57 3
  • Truncate 0.3 sec from an audio file using sox

    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
  • Print a row of 50 hyphens


    -2
    printf "%.50d" 0 | tr 0 -
    sata · 2010-03-25 12:52:45 3
  • Print a row of 50 hyphens

    essentially the ruby one, but perhaps has a larger installed base


    9
    python -c 'print "-"*50'
    funky · 2010-03-25 11:09:30 6
  • Print a row of 50 hyphens

    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
  • Show top SVN committers for the last month


    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
  • Print a row of 50 hyphens

    Get there by going backwards and forgetting the numbers.


    5
    seq -s" " -50 -1 | tr -dc -
    DoNotRememberMe · 2010-03-25 06:00:24 32
  • Dump an rpm's package details (besides the files)

    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
  • Capture and re-use expensive multi-line output in shell

    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
  • Change attributes of files so you can edit them

    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
  • List manually installed packages (excluding Essentials)


    2
    aptitude search '~i!~E' | grep -v "i A" | cut -d " " -f 4
    XORwell · 2010-03-25 00:40:51 6
  • Save a file you edited in vim without the needed permissions (no echo)

    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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Find and display most recent files using find and perl
This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

Put public IP address in a variable

list files recursively by size

Scans for open ports using telnet

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Create a thumbnail from a video file

Monitor memory fine-grained usage (e.g. firefox)
Sometimes top/htop don't give the fine-grained detail on memory usage you might need. Sum up the exact memory types you want

Clear terminal Screen

user 'tr' to convert mixed case in a file to lower case
convert mixed case in a file to lower case

drop first column of output by piping to this

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