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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 726 results
wmic OS get OSArchitecture /value | grep -Eo '[^=]*$'
2014-03-15 02:04:08
User: lowjax
Functions: get grep

Using "wmic get * /value" within any Cygwin shell will return lots of Win/Dos newline junk ie "^M$" at the end of found value line, two lines ("$" Unix newline) above, and three below. This makes storing and or evaluating wmic queries as variables a pain. The method i suggest strips the mentioned junk, only returns the value after "OSArchitecture=", and includes only one Unix style newline. Other methods using sed|awk|cut can only handle the output of wmic cleanly when piped or using multiple sed statements.

wmic OS get OSArchitecture /value | sed 's/\r//g;s/^M$//;/^$/d;s/.*=//'


wmic OS get OSArchitecture /value | grep -Eo '[^=]*$'

a much cleaner and slightly less costly alternative.

bashrc-reload() { builtin unalias -a; builtin unset -f $(builtin declare -F | sed 's/^.*declare[[:blank:]]\+-f[[:blank:]]\+//'); . ~/.bashrc; }
2014-03-02 14:24:18
User: Xk2c
Functions: sed unalias unset

Simply sourcing .bashrc does not function correctly when you edit it and change an alias for a function or the other way round with the *same name*.

I therefor use this function. Prior to re-sourcing .bashrc it unsets all aliases and functions.

tput rmam
2014-02-26 07:06:37
User: kennyld
Functions: tput
Tags: bash ksh
tput rmam

will disable line wrapping so that long lines are truncated to width of the terminal ($COLUMNS).

tput smam

will re-enable wrapping.

I've always used tput in bash scripts but I guess it works on the command line too.

Doesn't work in all terminals.

See http://www.gnu.org/software/termutils/manual/termutils-2.0/html_chapter/tput_1.html

printf -- " -e %s" ${ARRAY[*]}
2014-02-25 03:34:12
User: SEJeff
Functions: printf

[jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small

docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small

Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

ps -eo pmem,comm | grep application-name
2014-02-23 13:21:29
User: Darkstar
Functions: grep ps

Displays memory usage for individual instances of an application that spawns multiple instances of itself. This command also works on single process applications.

(read -r passphrase; b58encode 80$( brainwallet_exponent "$passphrase" )$( brainwallet_checksum "$passphrase" ))

A bitcoin "brainwallet" is a secret passphrase you carry in the "wallet" of your brain.

The Bitcoin Brainwallet Private Key Calculator calculates the standard base58 encoded bitcoin private key from your "brainwallet" passphrase.

The private key is the most important bitcoin number. All other numbers can be derived from it.

This command uses 3 other functions - all 3 are defined on my user page:

1) brainwallet_exponent() - search for Bitcoin Brainwallet Exponent Calculator

2) brainwallet_checksum() - search for Bitcoin Brainwallet Exponent Calculator

3) b58encode() - search for Bitcoin Brainwallet Base58 Encoder

Do make sure you use really strong, unpredictable passphrases (30+ characters)!

http:brainwallet.org can be used to check the accuracy of this calculator.

function b58encode () { local b58_lookup_table=({1..9} {A..H} {J..N} {P..Z} {a..k} {m..z}); bc<<<"obase=58;ibase=16;${1^^}"|(read -a s; for b58_index in "${s[@]}" ; do printf %s ${b58_lookup_table[ 10#"$b58_index" ]}; done); }

A bitcoin "brainwallet" is a secret passphrase you carry in your brain.

The Bitcoin Brainwallet Private Key Base58 Encoder is the third of three functions needed to calculate a bitcoin PRIVATE key from your "brainwallet" passphrase.

This base58 encoder uses the obase parameter of the amazing bc utility to convert from ASCII-hex to base58. Tech note: bc inserts line continuation backslashes, but the "read s" command automatically strips them out.

I hope that one day base58 will, like base64, be added to the amazing openssl utility.

find . -mtime +30 -exec mv {} old/ \;
2014-02-09 23:05:41
User: minnmass
Functions: find mv
Tags: bash file

Use find's built-in "exec" option to avoid having to do any weirdness with quoting.

quickscript () { filename="$1"; history | cut -c 8- | sed -e '/^###/{h;d};H;$!d;x' | sed '$d' > ${filename:?No filename given} }
2014-02-09 12:19:29
User: joedhon
Functions: cut sed

In order to write bash-scripts, I often do the task manually to see how it works. I type ### at the start of my session.

The function fetches the commands from the last occurrence of '###', excluding the function call. You could prefix this with a here-document to have a proper script-header.

Delete some lines, add a few variables and a loop, and you're ready to go.

This function could probably be much shorter...

for i in $(find . -mtime +30); do mv $i old/; done
2014-02-05 01:24:45
User: valferon
Functions: find mv
Tags: bash file

Will move in that case every file in the current folder older than 30 days to the "old" folder

Replace "mv $i old/" by any command such as rm / echo to do something different.

CMD=chrome ; ps h -o pmem -C $CMD | awk '{sum+=$1} END {print sum}'
rsstail -o -n 1 --f 'RedditQuote: {title}' http://www.reddit.com/r/quotes/new/.rss
2014-01-08 15:33:48
User: Youpfu

The rsstail is the python version (python-rsstail). The final command pipe it on every new line to gammu and a connected phone

rsstail -o -n 1 --f 'RedditQuote: {title}' http://www.reddit.com/r/quotes/new/.rss | while read line; do /usr/bin/gammu --sendsms TEXT +*yournumber* -text "$line"; done
watch -n 10 free -m
2014-01-04 10:10:15
User: Darkstar
Functions: free watch

This command shows a high level overview of system memory and usage refreshed in seconds. Change -n 10 to you desired refresh interval.

ps -eo pmem,comm | grep chrome | cut -d " " -f 2 | paste -sd+ | bc
2014-01-03 15:33:16
User: Darkstar
Functions: cut grep paste ps

This command will show the sum total of memory used in gigabytes by a program that spawns multiple instances of itself. Replace chrome with whatever program's memory usage you are investigating. This command is rather useless on software that only spawns a single instance of itself.

alias ?=concalc
2014-01-02 01:46:44
User: boynux
Functions: alias

Same functionality without using bash functions.

for i in */; do echo $(find $i -type f -regextype posix-extended -regex ".*\.(mp3|ogg|wav|flac)" | wc -l) $i ; done
find . -type d -maxdepth 1 -print0 | xargs -0 -I{} sh -c 'find "{}" -type f | grep "ogg\|mp3\|wav\|flac$" | wc -l | tr -d "\n"; echo " {}"'
2013-12-22 13:40:29
User: dbrgn
Functions: echo find grep sh tr wc xargs

This lists the number of ogg/mp3/wav/flac files in each subdirectory of the current directory. The output can be sorted by piping it into "sort -n".

bind -P | grep -v "is not" | sed -e 's/can be found on/:/' | column -s: -t
2013-12-19 12:30:19
User: leni536
Functions: column grep sed

Shows all available keyboard bindings in bash. Pretty printing.

ls -d .??*
2013-12-17 19:06:30
User: pydave
Functions: ls
Tags: bash glob

You can omit the -d to see what's inside directories. In that case, you may want -a to see dotfiles inside those directories. (Otherwise you don't need -a since you're explicitly looking at them.)

rpm -qa --queryformat '%{SIZE}\n' | awk '{sum += $1} END {printf("Total size in packages = %4.1f GB\n", sum/1024**3)}'
2013-12-14 20:22:41
User: skytux
Functions: awk rpm

It is not the installed size in files, but the size of RPM packages.

grep -c "search_string" /path/to/file
2013-12-10 18:13:54
User: meatflag
Functions: grep

-c will count the number of times your search matches in the file.

alias ltmux="if tmux has-session -t $USER; then tmux attach -t $USER; else tmux new -s $USER; fi"
2013-12-10 14:46:28
Functions: alias
Tags: bash alias sh tmux

If a session with named the same as your username already exists, then attach to it, otherwise create it

for i in */; do echo run_command "${i}"; done
2013-11-25 18:33:26
User: mirams
Functions: echo

Change the "run_command" to whatever command you want, and remove the "echo" to run it once you are happy.

nc -kl 5432 -c 'echo -e "HTTP/1.1 200 OK\r\n$(date)\r\n\r\n";echo "<p>How are you today?</p>"'
2013-11-12 14:00:11
User: gvitalie
Functions: echo

-k, --keep-open will keep connection alive, and we could exclude using 'while true'

nc is such a powerful command, it could be used instead of any OS! :p

curl ipinfo.io/<ipaddress>