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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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Boot without CD-Rom:
qemu fedora.qcow -boot c -net nic -net user -m 196 -localtime
Modify the script for your username and password, and save it as a script. Run the script, and enjoy ./tweet
This is the simple revision number on stdout, that can be fed to any useful/fun script of yours. Setting LC_ALL is useful if you use another locale, in which case "Revision" is translated and cannot be found. I use this with doxygen to insert my source files revisions into the doc. An example in Doxyfile:
FILE_VERSION_FILTER = "function svn_filter { LC_ALL=C svn info $1 | grep Revision | awk '{print $2}'; }; svn_filter"
Share your ideas about what to do with the revision number !
Use this if you can't type repeated killall commands fast enough to kill rapidly spawning processes.
If a process keeps spawning copies of itself too rapidly, it can do so faster than a single killall can catch them and kill them. Retyping the command at the prompt can be too slow too, even with command history retrieval.
Chaining a few killalls on single command line can start up the next killall more quickly. The first killall will get most of the processes, except for some that were starting up in the meanwhile, the second will get most of the rest, and the third mops up.
This grabs all lines that make an instantation or static call, then filters out the cruft and displays a summary of each class called and the frequency.
Identical output but a different way without having to shoot with the Awk cannon :)
Ummmm.. Saw that gem on some dead-head hippies VW bus at phish this summer.. It's actually one of my favorite ways of using bash, very clean. It shows what you can do with the cool advanced features like job control, redirection, combining commands that don't wait for each other, and the thing I like the most is the use of the ( ) to make this process heirarchy below, which comes in very handy when using fifos for adding optimization to your scripts or commands with similar acrobatics.
F UID PID PPID WCHAN RSS PSR CMD
1 gplovr 30667 1 wait 1324 1 -bash
0 gplovr 30672 30667 - 516 3 \_ sleep 3
1 gplovr 30669 1 wait 1324 1 -bash
0 gplovr 30673 30669 - 516 0 \_ sleep 5
1 gplovr 30671 1 wait 1324 1 -bash
0 gplovr 30674 30671 - 516 1 \_ sleep 7
It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.
Depending on the installation only certain of these man pages are installed. 12 is left out on purpose because ISO/IEC 8859-12 does not exist. To also access those manpages that are not installed use opera (or any other browser that supports all the character sets involved) to display online versions of the manpages hosted at kernel.org:
for i in $(seq 1 11) 13 14 15 16; do opera http://www.kernel.org/doc/man-pages/online/pages/man7/iso_8859-$i.7.html; done
This takes quite a while on my system. You may want to test it out with /bin first, or background it and keep working.
If you want to get rid of the "No manual entry for [whatever]" and just have the [whatever], use the following sed command after this one finishes.
sed -n 's/^No manual entry for \(.*\)/\1/p' nomanlist.txt
an extension of command 9986 by c3w, allows for link text.
http://google.com,search engine
will link the hyperlink with the text after the url instead of linking with the url as linktext
xargs avoids having to remember the "{} \;" (although definitely a useful thing to know. Unfortunately I always forget it). xargs version runs 2x faster on my test fwiw.
edit: fixed to handle spaces in filenames correctly.
You are probably aware that some percent of disk space on an ext2/ext3 file system is reserved for root (typically 5%). As documented elsewhere this can be reduced to 1% with
tune2fs -m 1 /dev/sdX (where X = drive/partition, like /dev/sda1)
but how do you check to see what the existing reserved block percentage actually is before making the change? You can find that with
dumpe2fs -h /dev/sdX
You get a raw block count and reserved block count, from which you can calculate the percentage. In the example here you can easily see that it's currently 1%, so you won't get any more available space by setting it to 1% again.
FYI If your disks are IDE instead of SCSI, your filesystems will be /dev/hdX instead of /dev/sdX.
This will allow you to mount a CD-ROM on Solaris SPARC 9 or lower. This will not work on Solaris 10 due to void and the volume management daemons.
Mount a Windows share. Usually the IP is needed for the $ip_or_host option. Getting hostnames working on a local network never seems to work.