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Terminal - All commands - 11,926 results
ping -i 60 -a IP_address
2009-03-04 06:21:22
User: haivu
Functions: ping
Tags: Network
100

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
-4

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
124

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
25

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

also:

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
1

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
2

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
8

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
1

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
2

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
:g!/\S/d
2009-03-02 23:58:45
User: leonza99
Tags: vim
16

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
2

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
1

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
3

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

awk -F "=| "
2009-03-02 21:09:51
User: Bender
Functions: awk cat file
9

You can use multiple field separators by separating them with | (=or).

This may be helpful when you want to split a string by two separators for example.

#echo "one=two three" | awk -F "=| " {'print $1, $3'}

one three

alias vb='vim ~/.bashrc; source ~/.bashrc'
2009-03-02 21:01:49
User: haivu
Functions: alias col groff man
2

Place the line above in your ~/.bahsrc file. Now every time you issue the 'vb' command, you invoke the vim editor to edit it, then source it so the changes take effect immediately.

Notes:

* This mechanism is not working well if your .bashrc contains commands that should not be sourced more than once.

* This trick also work for your csh or tclsh users: place the following line in your ~/.cshrc file:

alias vc 'vim ~/.cshrc; source ~/.cshrc

Thank you adzap for pointing out the missing quote

:n,m w newfile.txt
2009-03-02 19:40:34
User: milmazz
Tags: vim perl
8

On command mode in Vim you can save parts of the current buffer in another file.

* The 'n' value represents the first line of the new file.

* The 'm' value represents the last line of the new file.

* newfile.txt is the newfile.

The results are similar to this command in perl:

perl -ne 'print if n..m' in.sql > out.sql
rehash
2009-03-02 19:03:07
User: Pistos
1

Immediately after installing things into your PATH (e.g. under /usr/bin), currently open shells cannot find them ("zsh: command not found"). Use rehash to get the shell to rescan available executables.