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.. ;)
Nice interface for an info page.
A great way of viewing some man page while using gnome.
This requires that your sudo not prompt for a password, as sftp cannot allocate the terminal necessary to ask.
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 :)
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.
On Fedora clean the boot directory; erase older kernel
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 $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
Show Sample Output
This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use:
sudo dpkg --set-selections < LIST_FILE
Show Sample Output
Update a Mandriva Linux system with any pending updates. This command needs to be run with root privilege. Using the "--force" option answers "yes" to any interactive prompts thus allowing the updates to be left unattended to completion. NB if there is an update for glibc and/or a new kernel then the system would need to be rebooted for these to take effect. A prerequisite for running "urpmi --auto-update" is to have correctly defined urpmi media sources (which can be done by visiting http://easyurpmi.zarb.org/). If there are no new updates the the message "Packages are up to date" is shown. Show Sample Output
I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root):
dmidecode | awk '/Battery/,/^$/'
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.
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.
Perform a dns zone transfer (if is allowed on target dns server) and print result.
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
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).
Not so useful. Just a cool feature.
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.
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).
A great password generation tool. http://www.adel.nursat.kz/apg/ Show Sample Output
Within vi allow to empty a text file in one shot
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
head by default displays first ten lines of its output. Use 'head -nXX' to display the XX largest files
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