All commands (14,187)

  • Extremely useful to maintain backups if you're using Dropbox. This mirrors the entire directory structure and places symlinks in each to the original file. Instead of copying over the data again to the ~/Dropbox folder creating a symbolic link tree is much more sensible in terms of space usage. This has to be supplemented by another script that removes dead symlinks in the Dropbox folder which point to files that have been moved/removed. find -L ./ -type l -delete And then removing empty directories find ./ -type d -exec rmdir 2>/dev/null {} \; **Actually after some finding I found lndir which creates symbolic trees but it wasn't in the Arch repos so.. ;)


    0
    find /home/user/doc/ -type d -printf "mkdir -vp '/home/user/Dropbox%p'\n" -o -type f -printf "ln -vs '%p' '/home/user/Dropbox%p'\n" | sh
    jnash · 2009-03-29 09:25:12 23
  • Nice interface for an info page.


    1
    yelp info:foo
    renich · 2009-03-29 07:14:48 7
  • A great way of viewing some man page while using gnome.


    3
    yelp man:foo
    renich · 2009-03-29 07:13:44 8
  • This requires that your sudo not prompt for a password, as sftp cannot allocate the terminal necessary to ask.


    0
    sftp -s "sudo /usr/lib/sftp-server" user@host
    mrtheplague · 2009-03-29 07:02:58 6
  • Might be more useful if you were able to print it in Days HH:MM:SS format as: perl -e '@p=gmtime(234234);printf("%d Days %02d:%02d:%02ds\n",@p[7,2,1,0]);' But I'm not exactly sure how to replace the 234234 with the output of the countdown time. (Having some problems with nested quoting/command substitution). Help would be appreciated :)


    0
    watch --no-title -d -n 1 'echo `date -d "next Thursday" +%s` "-" `date +%s` | bc -l'
    jnash · 2009-03-29 06:53:09 9

  • 3
    dscacheutil -flushcache
    oarmas · 2009-03-29 06:17:32 5
  • Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing: grep kernel /var/log/messages Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for: < /var/log/messages grep kernel If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word. If this has already been submitted, I couldn't find it with the search utility.


    15
    < /path/to/file.txt grep foo
    atoponce · 2009-03-29 02:43:40 16
  • On Fedora clean the boot directory; erase older kernel


    1
    rpm -q kernel-2* | grep -v $(uname -r) | xargs yum erase -y
    Nick · 2009-03-28 21:41:15 11
  • Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount. BSD Version: netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr Show Sample Output


    14
    netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
    tiagofischer · 2009-03-28 21:02:26 73
  • This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use: sudo dpkg --set-selections < LIST_FILE Show Sample Output


    11
    dpkg --get-selections > LIST_FILE
    o6291408 · 2009-03-28 17:45:29 12
  • Update a Mandriva Linux system with any pending updates. This command needs to be run with root privilege. Using the "--force" option answers "yes" to any interactive prompts thus allowing the updates to be left unattended to completion. NB if there is an update for glibc and/or a new kernel then the system would need to be rebooted for these to take effect. A prerequisite for running "urpmi --auto-update" is to have correctly defined urpmi media sources (which can be done by visiting http://easyurpmi.zarb.org/). If there are no new updates the the message "Packages are up to date" is shown. Show Sample Output


    0
    urpmi --auto-update --force # apply all pending updates (Mandriva Linux)
    mpb · 2009-03-28 14:59:26 8
  • I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root): dmidecode | awk '/Battery/,/^$/' Will show me everything following the battery block up to the next block of text. Again, I find this extremely useful when I want to see whole blocks of text based on a pattern, and I don't care to see the rest of the data in output. This could be used against the '/etc/securetty/user' file on Unix to find the block of a specific user. It could be used against VirtualHosts or Directories on Apache to find specific definitions. The scenarios go on for any text formatted in a block fashion. Very handy.


    94
    awk '/start_pattern/,/stop_pattern/' file.txt
    atoponce · 2009-03-28 14:28:59 26
  • Packages: gmailfs fuse-utils libfuse2 gvfs-fuse Config files: /etc/gmailfs/gmailfs.conf; ~/.gmailfs.conf (make a copy from the another one) Unmount: fusermount -u /mount/path/ /etc/fstab (Optional): none /mount/path/ gmailfs noauto,user[,username=USERNAME,password=PASSWORD,fsname=VOLUME] 0 0 NOTES: - The options between [] are optional since they already setuped on the config files. - The '-p' flag shows a prompt for the password entry. - It's necessary to add the user to the 'fuse' group. You can do that with: sudo chgrp fuse /dev/fuse and sudo usermod -a -G fuse USER - The volume name is not needed but highly recommended to avoid file corruption. Also choose a non-trivial name. - Google doesn't approve the use of Gmail account other than e-mail purposes. So, I recommend the creation of a new account for this.


    5
    mount.gmailfs none /mount/path/ [-o username=USERNAME[,password=PASSWORD][,fsname=VOLUME]] [-p]
    o6291408 · 2009-03-28 13:00:47 5
  • Perform a dns zone transfer (if is allowed on target dns server) and print result.


    0
    host -la domain.com
    servermanaged · 2009-03-28 12:15:16 5
  • See: "man pwgen" for full details. Some Linux distros may not have pwgen included in the base distribution so you maye have to install it (eg in Mandriva Linux: "urpmi pwgen"). Show Sample Output


    6
    pwgen
    mpb · 2009-03-28 11:43:21 5
  • To install a theme use: sudo firefox -install-global-theme /path/to/theme You can get the .xpi or .jar file from the versions history on the add-on/theme page. NOTE: may not work in your system (Debian-based is an example).


    17
    sudo firefox -install-global-extension /path/to/add-on
    o6291408 · 2009-03-28 11:11:12 9
  • Not so useful. Just a cool feature.


    7
    mplayer -vo aa <video file>
    o6291408 · 2009-03-28 10:01:56 9
  • The download content part. NOTE: the '-c' seems to not work very well and the download stuck at 99% sometimes. Just finish wget with no problem. Also, the download may restart after complete. You can also cancel. I don't know if it is a wget or Rapidshare glitch since I don't have problems with Megaupload, for example. UPDATE: as pointed by roebek the restart glitch can be solved by the "-t 1" option. Thanks a lot.


    6
    wget -c -t 1 --load-cookies ~/.cookies/rapidshare <URL>
    o6291408 · 2009-03-28 09:13:35 5
  • In order to do that, first you need to save a cookie file with your account info. These commands do it (maybe you need to create the '.cookies' dir before). Also, you need to check the "Direct downloads" option on the Premium Zone >> Settings tab. You need to do this once (as long you maintain the file or your Rapidshare Premium account).


    4
    wget --save-cookies ~/.cookies/rapidshare --post-data "login=USERNAME&password=PASSWORD" -O - https://ssl.rapidshare.com/cgi-bin/premiumzone.cgi > /dev/null
    o6291408 · 2009-03-28 09:12:02 7
  • A great password generation tool. http://www.adel.nursat.kz/apg/ Show Sample Output


    3
    apg -a 0 -n 10
    renich · 2009-03-28 08:52:59 8
  • Within vi allow to empty a text file in one shot


    3
    :1,$d
    acirulli · 2009-03-28 02:28:19 12
  • The vi key sequence !}command will send the file contents from the cursor to the next blank line as STDOUT to the command specified and replace that sequence of file lines with the output of the command. For example: sorting a block of data - !}sort The sequence !{command will do the same but "upwards" (from the current position towards the start of the file. Show Sample Output


    12
    !}sort
    mpb · 2009-03-28 00:18:39 11

  • -13
    chmod +x FILES
    colinpj · 2009-03-27 23:28:40 5

  • -4
    sudo chmod -R g=u-w,g+X *
    mudiarto · 2009-03-27 23:27:12 5
  • head by default displays first ten lines of its output. Use 'head -nXX' to display the XX largest files


    -4
    ls -Sl * | head
    colinpj · 2009-03-27 23:20:32 7
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Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

notify brightness level [custom]
Brightness indicator to be used in scripts that adjust brightness [especially sys that doesn't support automatically]

get all Amazon cloud (amazonws etc) ipv6 subnets

Convert epoch date to human readable date format in a log file.

Wait for file to stop changing
This loop will finish if a file hasn't changed in the last 10 seconds. . It checks the file's modification timestamp against the clock. If 10 seconds have elapsed without any change to the file, then the loop ends. . This script will give a false positive if there's a 10 second delay between updates, e.g. due to network congestion . How does it work? 'date +%s' gives the current time in seconds 'stat -c %Y' gives the file's last modification time in seconds '$(( ))' is bash's way of doing maths '[ X -lt 10 ]' tests the result is Less Than 10 otherwise sleep for 1 second and repeat . Note: Clever as this script is, inotify is smarter.

Adhoc tar backup
Creates a quick backup with tar to a remote host over ssh.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

see the TIME_WAIT and ESTABLISHED nums of the network
see the TIME_WAIT and ESTABLISHED nums of the network


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