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Terminal - All commands - 12,230 results
mencoder -vf rotate=1 -ovc lavc -oac copy "$1" -o "$1"-rot.avi
mencoder "$1" -ofps 23.976 -ovc lavc -oac copy -o "$1".avi
vi -R filename
2009-03-04 06:56:40
User: haivu
Functions: vi
Tags: vim

The -R flag prevents you from making changes to a file, useful when you only want to view the file. This command is nicer than the 'more' or 'less' commands because for source codes, vi shows syntax highlight.

cal | grep --before-context 6 --after-context 6 --color -e " $(date +%e)" -e "^$(date +%e)"
2009-03-04 06:46:52
User: haivu
Functions: cal grep
Tags: PIM


* The date command evaluated to today's date with blank padded on the left if single digit

* The grep command search and highlight today's date

* The --before-context and --after-context flags displays up to 6 lines before and after the line containing today's date; thus completes the calendar.

I have tested this command on Mac OS X Leopard and Xubuntu 8.10

ping -i 60 -a IP_address
2009-03-04 06:21:22
User: haivu
Functions: ping
Tags: Network

Waiting for your server to finish rebooting? Issue the command above and you will hear a beep when it comes online. The -i 60 flag tells ping to wait for 60 seconds between ping, putting less strain on your system. Vary it to your need. The -a flag tells ping to include an audible bell in the output when a package is received (that is, when your server comes online).

ping -c 10 hostname
2009-03-04 06:14:52
User: haivu
Functions: ping
Tags: Network

On Linux and Mac systems (I have not tested with other Unix systems), the ping command will keep on pinging until the user interrupts it with Ctrl+C. On Windows system, ping will execute for a number of times then quit. The -c flag on Linux and Mac will make this happen

ssh -t reachable_host ssh unreachable_host
2009-03-03 23:21:36
User: patko
Functions: ssh
Tags: ssh

Unreachable_host is unavailable from local network, but it's available from reachable_host's network. This command creates a connection to unreachable_host through "hidden" connection to reachable_host.

LC_ALL=fr_FR luit ssh root@remote_machine_ip
jhead -autorot *.jpg
watch -n 5 -d cat /proc/mdstat
$ grep -rl oldstring . |xargs sed -i -e 's/oldstring/newstring/'
2009-03-03 20:10:19
User: netfortius
Functions: grep sed
Tags: perl sed

recursively traverse the directory structure from . down, look for string "oldstring" in all files, and replace it with "newstring", wherever found


grep -rl oldstring . |xargs perl -pi~ -e 's/oldstring/newstring'
xset dpms force standby
urpmf lib/blah
2009-03-03 16:21:52
User: ender_x
Tags: mandriva urpmi

Look for an rpm that supplies a specific file that you don't yet have installed.

extremely useful when you need something and don't know where it is.. or what its called.

note: uses grep like syntax.

for i in *.html ; do mv $i ${i%.html}.htm ; done
emacs +400 code.py
2009-03-03 14:30:19
User: prayer
Functions: emacs
Tags: emacs

You may also use +line:column syntax.

zgrep "Failed password" /var/log/auth.log* | awk '{print $9}' | sort | uniq -c | sort -nr | less
2009-03-03 13:45:56
User: dbart
Functions: awk sort uniq zgrep

This command checks for the number of times when someone has tried to login to your server and failed. If there are a lot, then that user is being targeted on your system and you might want to make sure that user either has remote logins disabled, or has a strong password, or both. If your output has an "invalid" line, it is a summary of all logins from users that don't exist on your system.

gunzip -c /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log.0 | grep "Invalid user" | awk '{print $8;}' | sort | uniq -c | less
vlc --one-instance --playlist-enqueue -q $(while read netcast; do wget -q $netcast -O - |grep enclosure | tr '\r' '\n' | tr \' \" | sed -n 's/.*url="\([^"]*\)".*/\1/p'|head -n1; done <netcast.txt)
2009-03-03 04:26:01
User: tomwsmf
Functions: read sed tr wget

This is a quick line to stream in the latest offerings of your favorite netcasts/podcasts. You will need to have a file named netcast.txt in the directory you run this from. This file should have one and only one of your netcast's/podcst's url per line.

When run the line grabs the offering on the top of the netcast/podcast stack and end it over , quietly, to vlc.

Since I move around computers during the day I wanted an easy way to listen to my daily dose of news and such without having to worry about downloading to whatever machine I am on. This is just a quick grab and stream of whats current.

Future plans... have the list of netcasts be read from the web. possibly an rss or such. I use greader so there might be a way to use it as the source so as not to have to muck with multiple lists

find / -name "*.jpg" -print -exec rdjpgcom '{}' ';'
2009-03-03 02:13:44
User: Williebee
Functions: find

Finds comments in jpg files, but I can't figure out how to exclude (in output) files without comments.

sed -i 8d ~/.ssh/known_hosts
2009-03-02 23:58:45
User: leonza99
Tags: vim

This command delete all the empty lines (include the lines with space) from a file.

g = global command

\S = non-whitespace character; !\S the opposite

d = delete a range

less +G <filename>
2009-03-02 23:34:21
User: leper421
Functions: less

The same as typing 'less filename' then 'G' or '>' or the END key. Comes in handy with shell scripts or aliases:

alias weblog='less +G /var/log/httpd/access_log'

alias errlog='less +G /var/log/httpd/error_log'

ifconfig -a | nawk 'BEGIN {FS=" "}{RS="\n"}{ if($1~ /:/) {printf "%s ", $1}}{ if($1=="inet") {print " -- ",system("arp "$2)}}'|egrep -v "^[0-9]$"
2009-03-02 23:15:13
User: leprasmurf
Functions: ifconfig

Needed to get the Mac of various devices on a solaris box, but didn't have root. This command used awk to display the Network device, the IP, and the MAC a line at a time.

:set ic
ssh -T user@host /bin/bash -i
2009-03-02 21:39:30
User: Bender
Functions: ssh

opens a "hidden" remote shell (login will not appear in "last" for example).

This is not really hidden, because the login will be shown in auth.log and the process is visible anyways.

ssh -T = Disable pseudo-tty allocation.

bash -i = interactive shell