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Terminal - All commands - 11,998 results
find /home/dir -mtime +1 -print -exec gzip -9 {} \; -exec mv {}.gz {}_`date +%F`.gz \;
sudo tune2fs -m 1 /dev/sda4
2009-09-14 21:11:55
User: bassel
Functions: sudo tune2fs
2

According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition.

http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/

hdparm -t /dev/sda
: ${VAR:?unset variable}
2009-09-14 19:41:01
User: arcege
Tags: shell
-1

Works in all shells. Does not require a test. Handles like an assertion.

cdrecord -v -blank=all -force
cdrecord -v path_to_iso_image.iso
display "$(wget -q http://dynamic.xkcd.com/comic/random/ -O - | grep -Po '(?<=")http://imgs.xkcd.com/comics/[^"]+(png|jpg)')"
2009-09-14 18:40:14
User: syssyphus
Tags: wget xkcd
6

i sorta stole this from

http://www.shell-fu.org/lister.php?id=878#MTC_form

but it didn't work, so here it is, fixed.

---

updated to work with jpegs, and to use a fancy positive look behind assertion.

[ -z "$VAR" ] && echo "VAR has not been set" && exit 1
echo {1..3}" o'clock" ROCK
echo "$(</etc/issue)"
2009-09-14 09:44:35
User: mobidyc
Functions: echo
-2

another replacement for cat.

type <filename>
2009-09-14 09:37:23
User: danam
Functions: type
4

Also searches for aliases and shell builtins

ffmpeg -ss 0:58:15 -i DavidLettermanBlackCrowes.mpg -acodec copy DavidLettermanBlackCrowes.ac3
2009-09-14 00:08:36
User: PLA
3

There are some pretty good live performances on late night TV. With Mythtv I record David Letterman, Jimmy Fallon, and Conan nightly all in HD from over the air broadcasts. If I find a live performance I like I copy it to my Rockboxed iPod using this command. The Rockbox firmware knows how to downmix 5.1 audio. The command above extracts the audio from the video starting at 58 minutes and 15 seconds. It ends at the end of the file since this was the last performance of the recording. The command creates an ac3 file. I copy the ac3 file to my Rockbox iPod and rock on.

sed 's/^/$ /' "$script" | xclip
2009-09-13 11:21:54
User: intuited
Functions: sed
Tags: sed xclip meta
2

Assuming that $script contains the filename of a script you'd like to post as part of a comment on this site, this will prefix each line with '$' and pipe it into the X selection. From there just put the cursor in the right place in the comments box and middle-click.

Should work pretty much anywhere with xclip installed. On debian-ish systems this is installed as part of the package "xclip".

nm --dynamic <libfile.so>
2009-09-13 09:27:57
User: Vereb
Functions: nm
2

You can get what functions at which addresses are inside a dynamic link library by this tool.

echo foo | netcat 192.168.1.2 25
2009-09-13 01:33:02
User: pykler
Functions: echo
2

Using netcat, usuallly installed on debian/ubuntu.

Also to test against a sample server the following two commands may help

echo got milk? | netcat -l -p 25

python -c "import SocketServer; SocketServer.BaseRequestHandler.handle = lambda self: self.request.send('got milk?\n'); SocketServer.TCPServer(('0.0.0.0', 25), SocketServer.BaseRequestHandler).serve_forever()"

ssh -f user@remote.ip DISPLAY=:0.0 smplayer movie.avi
2009-09-12 22:16:59
User: Escher
Functions: ssh
7

Launch a gui app remotely. In this example smplayer is installed on the remote machine, and movie.avi is in the remote user's home dir. Note that stdout/stderr is still local, so you'll have feedback locally, add '&>/dev/null' to suppress. This is surprisingly not well known (compared to running an X app locally via ssh -X). (NB. if your distro requires ~/.Xauthority file present, then try -fX if you have problems)

Resubmitted (and trimmed, thanks sitaram) due to ridiculous voting on previous submission. Fingers crossed, it gets a better rating this time.

echo "foo" > /dev/tcp/192.168.1.2/25
2009-09-12 16:48:05
User: mobidyc
Functions: echo
23

this command will send a message to the socket 25 on host 192.168.1.2 in tcp.

works on udp and icmp

understand only IP address, not hostname.

on the other side (192.168.1.2), you can listen to this socket and test if you receive the message.

easy to diagnose a firewall problem or not.

find . \( ! -name . -prune \) \( -type f -o -type l \)
2009-09-12 15:58:56
User: mobidyc
Functions: find
1

you must be in the directory to analyse

report all files and links in the currect directory, not recursively.

this find command ahs been tested on hp-ux/linux/aix/solaris.

mencoder -sub subs.ssa -utf8 -subfont-text-scale 4 -oac mp3lame -lameopts cbr=128 -ovc lavc -lavcopts vcodec=mpeg4 -ffourcc xvid -o output.avi input.flv
2009-09-12 09:24:24
User: ivalladt
1

Gives MPEG-4/DivX output video file ready for uploading to YouTube from FLV file downloaded from the site and your own subtitle file UTF-8 encoded. No resizing needed. (?)

which <filename>
ssh user@machine_A dd if=/dev/dvd0 > dvddump.iso
2009-09-11 18:08:36
User: kamathln
Functions: dd ssh
Tags: ssh dvd dump
5

You can use this to directly dump from machine A (with dvd drive) to machine B (without dvd drive) . I used this to copy dvd using my friend's machine to my netbook. Above command is to be issued on machine B.

Advantages :

1) No wasting time dumping first to machine A and then copying to Machine B.

2) You dont need to use space on Machine A. In fact, this will work even when Machine A doesnt have enough hdd space to dump the DVD.

Use -C ssh option on slow networks (enables compression).

you can replace "dd if=/dev/dvd" with any ripping command as long as it spews the iso to stdout.

for i in *;do avidemux --video-codec Xvid4 --audio-codec mp3 --load "${i}" --save "`echo "$i" | sed -e 's/\....$//'`.done.mp4" --quit; done
2009-09-11 17:07:38
User: gean01
2

Convert multiple files using avidemux. Version updated (thanks to the guys who helped me giving me hints about how to improve the command). Works with files whose name contains blank characters.

One of the reasons why I love open source: everyone can take something "done" and improve it to make it better! If u have suggestions, please let me know.

file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i x86_64 |nl | tail -1 | cut -f1 -f3; file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i "mach-o object i386" |nl | tail -1 | cut -f1 -f3
2009-09-11 16:43:27
Functions: cut file grep nl tail
-2

Not as far off as you thought, now is it?

-mac fanboy

for L in `echo :$PATH | tr : '\n'`; do F=${L:-"."}/fileName; if [ -f ${F} -o -h ${F} ]; then echo ${F}; break; fi; done
2009-09-11 16:14:36
User: arcege
Functions: echo tr
-1

Searches in order of the directories of $PATH. Stops after finding the entry; looks for only that fileName. Works in Bourne, Korn, Bash and Z shells.

find . -maxdepth 1 ! -name '.' -execdir du -0 -s {} + | sort -znr | gawk 'BEGIN{ORS=RS="\0";} {sub($1 "\t", ""); print $0;}' | xargs -0 du -hs
2009-09-11 16:07:39
User: ashawley
Functions: du find gawk sort xargs
1

A little bit smaller, faster and should handle files with special characters in the name.