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--- linuxutils [2008/05/24 15:12] – 81.208.74.179
+++ linuxutils [2008/05/24 20:20] (current) – old revision restored 88.66.8.195
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+====== Useful Linux Utilities ======
+  * [[gpg]] options
+===== Useful tools with hard to remember names =====
+  * ''scrot -s'' -- takes screenshots of an area
+  * generates passwords:
+    - ''apg -a 1 -m 6 -x 6''
+    - ''pwgen''
+  * ''figlet foo'' -- creates an ASCII art formatted text
+===== Mrxvt =====
+[[http://materm.sourceforge.net/index.html|Mrxvt]] is a multitabbed terminal emulator based on RXVT. It doesn't require any heavy libraries like QT or GTK so it's ideal for a low powered laptop machine.
+Place this into your ''~/.Xdefaults'' file for some nicer defaults.
+<code>
+mrxvt.font: 9x15
+mrxvt.geometry: 100x30
+mrxvt.reverseVideo: True
+mrxvt.loginShell: True
+mrxvt.scrollbarRight: True
+mrxvt.scrollbarStyle: rxvt
+mrxvt.bottomTabbar: True
+mrxvt.saveLines: 1500
+mrxvt.visualBell: True
+Mrxvt.macro.Shift+Left: GotoTab -1
+Mrxvt.macro.Shift+Right: GotoTab +1
+</code>
+Some tips:
+  * Change tab with ''Shift+Right'' and ''Shift+Left''
+  * Open a new tab with ''Shift+Ctrl+t''
+  * Change the title of a tab by marking some text and middle click the tab's name
+  * Open multiple tabs at startup with ''-tnum #'' in command-line args
+===== SSH Port forwarding =====
+Forward the webserver (port 127.0.0.1:80) at remote.host to your local machine (port 8080) and allow open this port (8080) on all local interfaces (-g):
+  $> ssh user@remote.host -L 8080:127.0.0.1:80 -N -g
+===== File Transfer through existing SSH connection =====
+Have you ever been logged into a machine (maybe even over multiple hosts) and then needed a file from you local host on that machine? Using a second connection with scp is a pain in the a** especially with multiple hops. The solution is [[http://zssh.sourceforge.net/|zssh]] - a wrapper around SSH and the zmodem protocol.
+On you local machine just install it (''apt-get install zssh'' is your friend) and probably add the following to your ''~/.bashrc''
+  alias ssh=zssh
+When you are on the remote machine just press ''CTRL-Space'' to go into interactive mode (very much like FTP). To send a file use this:
+  sz -e <file>
+The ''-e'' option works around non 8-Bit clean terminals. You only need the ''lrzsz'' and ''ssh'' packages installed on the remote machine.
+===== vmstat =====
+Gives you some info about memory stats, IO and CPU states. Give sample rate in seconds as parameter.
+  #> vmstat 3
+===== dig =====
+This is a powerful replacement for ''nslookup''
+Doing a zone transfer if allowed:
+  $> dig @nameserver domain.tld axfr
+===== Unlocking a CD Writer with cdrdao =====
+If a write failes the writer stays inaccessable sometimes - giving an error like this:
+  logical unit not ready, long write in progress
+Resetting the SCSI or ATAPI bus doesn't help. The tool cdrdao has an option to reset the device properly:
+  #> cdrdao unlock
+<del>===== Copy an audio CD with cdrdao =====</del>
+Will use the recorder for reading and writing:
+  #> cdrdao copy --device 0,0,0 --driver generic-mmc --datafile /exchange/cd.img --eject
+===== Burn an ISO Image with cdrecord =====
+  #> cdrecord -v dev=0,0,0 speed=16 driveropts=burnfree image.iso
+===== VIM Setup in source file =====
+You can embed Setup Commands for VIM in the source file. Here is an example for a Shell Script:
+  #Setup VIM: ex: et ts=2 nowrap syntax=sh :
+===== pgrep and pkill =====
+From the [[man>pgrep|manpage]]:
+> pgrep  looks through the currently running processes and lists the process IDs which matches the selection criteria to stdout.  All the criteria have to match.  For example, ''pgrep -u root sshd'' will only list the processes called sshd AND owned by root.  On the other hand, ''pgrep -u root,daemon'' will list the processes owned by root OR daemon.
+>
+> pkill will send the specified signal (by default SIGTERM) to each process instead of listing them on stdout.
+This is a nice replacement for constructions like ''%%kill `ps ax|grep 'foo'|grep -v 'grep'|awk '{print $1}'`%%''
+===== nast =====
+Sweet Network Analyzer (http://nast.berlios.de/) or just install the Debian Packages.
+I like the ''-m'' (map LAN via ARP requests) and the ''-g'' (find a gateway host) switches most.
+===== iostat I/O Device Usage Informations =====
+This command-line tool is within the ''sysstat''-package and provides information about the cpu load/usage   and/or about basically any device in /dev/.
+usage: iostat [device [device2..]] [refrehrate in sec] [repeats]
+refrehsrate defaults to 0, means no repeats at all.
+repeat defaults to infinite.
+===== iptraf Network Load Informations =====
+This command-line tool displays package information and Usage of several network interfaces.
+It has a console-graphical interface and serveral configuration options. See man-page.
+===== httrack Website Copier =====
+To fetch a whole site use this command:
+  $> httrack -K0 -%q0 --keep-alive --urlhack -D http://www.example.com
+===== mplayer / mencoder =====
+This gives you the suggested crop parameters:
+  $> mplayer -vf cropdetect somemovie.avi
+This concats two avi files
+  $> cat part1.avi part2.avi| mencoder -noidx -ovc copy -oac copy -o output.avi -
+For rotating MJPEG movies as produced by the [[PowerShot S2 IS]]. This is not completely lossless but the best way I could find:
+  $> mencoder -vf rotate=2 -ovc lavc -lavcopts vcodec=mjpeg -oac copy -o output.avi input.avi