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Terminal - All commands - 12,069 results
sleeper(){ while `ps -p $1 &>/dev/null`; do echo -n "${2:-.}"; sleep ${3:-1}; done; }; export -f sleeper
12

Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes.

Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!;

The wait is also used here, though it may not be needed on your system.

echo ">>> ENCRYPTING SQL BACKUP" gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null

Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7)); CC[$i]="\033[1;3${i}m"; CC[$ii]="\033[0;3${i}m"; done
1

I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like:

echo -e "${CC[15]}This text is black on bright green background."

I usually just use with a function:

# setup_colors - Adds colors to array CC for global use # 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42' function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; }; export -f setup_colors

CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white.

CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m'

Those are just my favorite colors that I often use in my scripts. You can test which colors by running

for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done

See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.

cat filename | uuencode filename | mail -s "Email subject" [email protected]
2009-09-21 04:13:50
User: amaymon
Functions: cat mail uuencode
Tags: cat mail
0

uuencode the file to appear as an attachment

find -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
2009-09-21 00:24:14
User: syssyphus
Functions: find md5sum sort uniq xargs
58

This dup finder saves time by comparing size first, then md5sum, it doesn't delete anything, just lists them.

tar cpof - src |( cd des; tar xpof -)
2009-09-20 20:43:30
Functions: cd tar
-2

Using tape archive create a tar file in Stdout (-) and pipe that into a compound command to extract the tar file from Stdin at the destination. This similar to "Copy via tar pipe ...", but copies across file systems boundaries. I prefer to use cp -pr for copying within the same file system.

xcopy D:\*.* /s/e/f E:\
2009-09-20 12:36:52
User: eth0
-3

Replace D drive with mounted ISO virtual drive and Replace E with your USB drive letter.

gpg --allow-multiple-messages --decrypt-files *
2009-09-20 11:50:41
User: bkn390
Functions: gpg
1

Change directory (cd) to the directory where all your encrypted files are placed, and then run the command - then you are asked to insert your secret gpg password - ubuntu 8.04

netstat -an | awk '$1 ~ /[Tt][Cc][Pp]/ && $NF ~ /ESTABLISHED/{i++}END{print "Connected:\t", i}'
Ctrl-R <search-text>
2009-09-20 05:07:31
User: tarkasteve
Tags: bash tricks
14

Searches backwards through your command-history for the typed text. Repeatedly hitting Ctrl-R will search progressively further. Return invokes the command.

xmms2 mlib search added \> $(echo $(date +%s) - 604800|bc)
cat filename | mail -s "Email subject" [email protected]
2009-09-20 01:38:23
Functions: cat mail
Tags: cat mail
2

This just reads in a local file and sends it via email. Works with text or binary. *Requires* local mail server.

xev -id `xwininfo | grep 'Window id' | awk '{print $4}'`
2009-09-19 22:47:16
User: ktoso
Functions: awk grep
2

After executing this, click on a window you want to track X Window events in.

Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo"

ss -p
2009-09-19 21:55:01
User: Escher
46

for one line per process:

ss -p | cat

for established sockets only:

ss -p | grep STA

for just process names:

ss -p | cut -f2 -sd\"

or

ss -p | grep STA | cut -f2 -d\"
seq -s " " -w 3 20
echo $(date +%s) > start-time; URL=http://www.google.com; while true; do echo $(curl -L --w %{speed_download} -o/dev/null -s $URL) >> bps; sleep 10; done &
2009-09-19 21:26:06
User: matthewbauer
Functions: date echo sleep
9

This will log your internet download speed.

You can run

gnuplot -persist <(echo "plot 'bps' with lines")

to get a graph of it.

lsof -P -i -n | cut -f 1 -d " "| uniq | tail -n +2
(IFS=:;for p in $PATH; do test -d $p || echo $p; done)
2009-09-19 17:51:06
User: haivu
Functions: echo test
Tags: bash PATH
9

I often need to know of my directory in the PATH, which one DOES NOT exist. This command answers that question

* This command uses only bash's built-in commands

* The parentheses spawn a new sub shell to prevent the modification of the IFS (input field separator) variable in the current shell

(sp-sc sop://broker.sopcast.com:3912/6002 3900 8900 &>/dev/null &); sleep 10; mplayer http://localhost:8900/tv.asf
2009-09-19 17:46:13
User: Escher
Functions: sleep
1

Get sopcast links for live sports from http://myp2p.eu (for example)

Get sp-sc or sp-auth binary by googling (sopcast + linux)

eg http://www.jbg.f2s.com/sp-sc.gz

Requires the 32bit libstdc++5 package.

After exiting mplayer, type 'killall sp-sc'

netstat -lantp | grep -i stab | awk -F/ '{print $2}' | sort | uniq
2009-09-19 14:54:31
User: ProMole
Functions: awk grep netstat sort
7

Show apps that use internet connection at the moment.

Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes.

This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO")

netstat -lantp | grep -i establ | awk -F/ '{print $2}' | sort | uniq
netstat -lantp | grep -i establ | awk -F/ '{print $2}' | uniq | sort
2009-09-19 13:54:36
User: ktoso
Functions: awk grep netstat uniq
-1

Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.

Has anyone an idea why the uniq doesn't work propperly here (see sample output)?

echo -ne "\033]0;`id -un`:`id -gn`@`hostname||uname -n|sed 1q` `who -m|sed -e "s%^.* \(pts/[0-9]*\).*(\(.*\))%[\1] (\2)%g"` [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"` / `ps aux|wc -l`]\007"
2009-09-19 06:57:53
User: AskApache
Functions: echo
4

I usually have 5 or more ssh connections to various servers, and putting this command in my .bash_profile file makes my putty window or x terminal window title change to this easily recognizable and descriptive text. Includes the username, group, server hostname, where I am connecting from (for SSH tunneling), which device pts, current server load, and how many processes are running.

You can also use this for your PROMPT_COMMAND variable, which updates the window title to the current values each time you exec a command.

I prefix running this in my .bash_profile with

[[ ! -z "$SSH_TTY" ]] &&

which makes sure it only does this when connecting via SSH with a TTY.

Here's some rougher examples from http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

# If set, the value is executed as a command prior to issuing each primary prompt. #H=$((hostname || uname -n) 2>/dev/null | sed 1q);W=$(whoami) #export PROMPT_COMMAND='echo -ne "\033]0;${W}@${H}:${PWD/#$HOME/~} ${SSH_TTY/\/dev\//} [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"`]\007"' #PROMPT_COMMAND='echo -ne "\033]0;`id -un`:`id -gn`@`hostname||uname -n 2>/dev/null|sed 1q` `command who -m|sed -e "s%^.* \(pts/[0-9]*\).*(\(.*\))%[\1] (\2)%g"` [`uptime|sed -e "s/.*: \([^,]*\).*/\1/" -e "s/ //g"` / `command ps aux|wc -l`]\007"' #[[ -z "$SSH_TTY" ]] || export PROMPT_COMMAND #[[ -z "$SSH_TTY" ]] && [[ -f /dev/stdout ]] && SSH_TTY=/dev/stdout

And here's a simple function example for setting the title:

function set_window_title(){ echo -e "\033]0; ${1:-$USER@$HOST - $SHLVL} \007"; }
for p in ${PATH//:/ }; do [[ -d $p && -x $p ]] && echo $p; done
2009-09-19 06:43:57
User: AskApache
Functions: echo
1

Finds executable and existing directories in your path that can be useful if migrating a profile script to another system. This is faster and smaller than any other method due to using only bash builtin commands.

See also:

+ http://www.commandlinefu.com/commands/view/743/list-all-execs-in-path-usefull-for-grepping-the-resulting-list

+ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

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