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Commands tagged function from sorted by
Terminal - Commands tagged function - 111 results
function every() { sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}; }
2015-04-03 01:30:36
User: flatcap
Functions: sed

Thanks to knoppix5 for the idea :-)

Print selected lines from a file or the output of a command.


every NTH MAX [FILE]

Print every NTH line (from the first MAX lines) of FILE.

If FILE is omitted, stdin is used.

The command simply passes the input to a sed script:

sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}

print no output

sed -n

quit after this many lines (controlled by the second parameter)

-e "${2}q"

print every NTH line (controlled by the first parameter)

-e "0~${1}p"

take input from $3 (if it exists) otherwise use /dev/stdin

function every() { N=$1; S=1; [ "${N:0:1}" = '-' ] && N="${N:1}" || S=0; sed -n "$S~${N}p"; }
2015-03-21 23:44:59
User: flatcap
Functions: sed

Sometimes commands give you too much feedback.

Perhaps 1/100th might be enough. If so, every() is for you.

my_verbose_command | every 100

will print every 100th line of output.

Specifically, it will print lines 100, 200, 300, etc

If you use a negative argument it will print the *first* of a block,

my_verbose_command | every -100

It will print lines 1, 101, 201, 301, etc

The function wraps up this useful sed snippet:

... | sed -n '0~100p'

don't print anything by default

sed -n

starting at line 0, then every hundred lines ( ~100 ) print.


There's also some bash magic to test if the number is negative:

we want character 0, length 1, of variable N.


If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

crontest () { date +'%M %k %d %m *' |awk 'BEGIN {ORS="\t"} {print $1+2,$2,$3,$4,$5,$6}'; echo $1;}
2015-03-12 19:56:56
User: CoolHand
Functions: awk date echo

usage = crontest "/path/to/bin"

This version of this function will echo back the entire command so it can be copied/pasted to crontab. Should be able to be automagically appended to crontab with a bit more work. Tested on bash and zsh on linux,freebsd,aix

findfile() { find . -type f -iname "*${*}*" ; }
2015-01-01 03:15:51
User: Xk2c
Functions: find
Tags: find function

Actually your func will find both files and directorys that contain ${1}.

This one only find files.

..and to look only for dirs:

finddir() { find . -type d -iname "*${*}*" ; }

psgrep() ... func to long, please look under "description"
2015-01-01 02:58:48
User: Xk2c
Functions: look
Tags: grep function ps

David thanks for that grep inside!

here is mine version:



case ${1} in

( -E | -e )


shift 1






if [[ -z ${*} ]]


echo "psgrep - grep for process(es) by keyword" >&2

echo "Usage: psgrep [-E|-e] ... " >&2

echo "" >&2

echo "option [-E|-e] enables full extended regexp support" >&2

echo "without [-E|-e] plain strings are looked for" >&2

return 1


\ps -eo 'user,pid,pcpu,command' w | head -n1

local ARG=''

if (( ${EXTENDED_REGEXP} == 0 ))


while (( ${#} > 0 ))



shift 1

local STRING=${ARG}

local LENGTH=$(expr length ${STRING})

local FIRSCHAR=$(echo $(expr substr ${STRING} 1 1))

local REST=$(echo $(expr substr ${STRING} 2 ${LENGTH}))

\ps -eo 'user,pid,pcpu,command' w | grep "[${FIRSCHAR}]${REST}"



\ps -eo 'user,pid,pcpu,command' w | grep -iE "(${*})"



psg(){ ps aux | grep -E "[${1:0:1}]${1:1}|^USER"; }
2015-01-01 00:12:45
User: flatcap
Functions: grep ps
Tags: grep function ps

Function that searchs for process by its name:

* Shows the Header for reference

* Hides the process 'grep' from the list

* Case sensitive

The typical problem with using "ps | grep" is that the grep process shows up the in the output.

The usual solution is to search for "[p]attern" instead of "pattern".

This function turns the parameter into just such a [p]attern.

${1:0:1} is the first character of $1


${1:1} is characters 2-end of $1
finame(){ find . -iname "*$1*"; }
2014-12-31 22:33:08
Functions: find
Tags: find function

It looks for files that contains the given word as parameter.

* case insensitive

* matches files containing the given word.

nohist(){ export HISTFILE=/dev/null; }
2014-12-31 22:30:08
Functions: export

Yo run the `nohist` command and after that the commands won't get stored in the history file for the current session.

This makes no permanent changes.

psg(){ ps aux | grep -v grep | egrep -e "$1|USER"; }
2014-12-31 22:27:27
Functions: egrep grep ps
Tags: grep function ps

Function that searchs a process by its name and shows in the terminal.

* Shows the Header for reference

* Hides the process 'grep' from the list

* Case sensitive

fn() { find . -iname "*$1*" -print; }
2014-07-15 05:30:59
User: suprjami
Functions: find

A simple bash function to the find command. I use this much more than find itself.

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.

function brainwallet_checksum () { (o='openssl sha256 -binary'; p='printf';($p %b "\x80";$p %s "$1"|$o)|$o|sha256sum|cut -b1-8); }

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

The Bitcoin Brainwallet Exponent Calculator is the second of three functions needed to calculate a bitcoin PRIVATE key. Roughly, checksum is the first 8 hex digits of sha256(sha256(0x80+sha256(passphrase)))

Note that this is a bash function, which means you have to type its name to invoke it

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

Same functionality without using bash functions.

function garg () { tail -n 1 ${HISTFILE} | awk "{ print \$$1 }" }
2013-09-10 04:07:46
User: plasticphyte
Functions: awk tail

This gets the Nth argument in the last line of your history file. This is useful where history is being written after each command, and you want to use arguments from the previous command in the current command, such as when doing copies/moving directories etc.

I wrote this after getting irritated with having to continually type in long paths/arguments.

You could also use $_ if all you want is the last argument.

function mkdcd () { mkdir "$1" && cd "$1" }
function createdb () { mysqladmin -u root -p create $1 && mysql -u root -p -e "GRANT ALL ON $1.* TO '$2'@'localhost' IDENTIFIED BY '$3';" ; }
2013-08-18 00:34:37
User: thanosme

Put this into your ~/.bashrc to create a database for mysql with a user and password.

Usage: createdb `database` `datbase-user` `database-password`.

function colorize() { c="--line-buffered --color=yes"; GREP_COLORS="mt=01;34" egrep $c '(^| 200 | 304 )' "${@}" | GREP_COLORS="mt=02;31" egrep $c '(^|"(GET|POST) .*[^0-9] 4[0-1][0-9] )' | GREP_COLORS="ms=02;37" egrep $c '(^|^[0-9\.]+) ';}
2013-08-14 21:05:34
User: mogsie
Functions: egrep

Puts a splash of color in your access logs. IP addresses are gray, 200 and 304 are green, all 4xx errors are red. Works well with e.g. "colorize access_log | less -R" if you want to see your colors while paging.

Use as inspiration for other things you might be tailing, like syslog or vmstat


tail -f access.log | colorize
open() { explorer /e, $(cygpath -wap "${1:-$PWD}"); }
2013-08-08 14:49:15
User: applemcg

use the shell default positional parameter syntax ${X:-default} in lieu of testing.

google() { gg="https://www.google.com/search?q=";q="";if [[ $1 ]]; then for arg in "$@" ; do q="$q+$arg"; done ; if [[ -f /usr/bin/chromium ]]; then chromium "$gg"$q; else firefox -new-tab "$gg"$q; fi else echo 'Usage: google "[seach term]"'; fi }
google() { gg="https://www.google.com/search?q="; ff="firefox"; if [[ $1 ]]; then "$ff" -new-tab "$gg"$(echo ${1//[^a-zA-Z0-9]/+}); else echo 'Usage: google "[seach term]"'; fi }
2013-08-01 22:21:53
User: lowjax
Functions: echo

Usage: google "[search string]"

Example: google "something im searching for"

This will launch firefox and execute a google search in a new tab with the provided search string.

You must provide the path to your Firefox binary if using cygwin to $ff or create an alias like follows:

alias firefox='/cygdrive/c/Program Files (x86)/Mozilla Firefox/firefox.exe'

Most Linux flavors with Firefox installed will use just ff="firefox" and even OSX.

rhost() { if [[ $1 =~ ^[0-9]+$ ]]; then sed -i "$1"d ${HOME}/.ssh/known_hosts; else echo "rhost [n]"; fi }
2013-08-01 21:10:34
User: lowjax
Functions: echo sed

Quickly remove the conflicting line (key) from current users known_hosts file when there is an SSH host conflict. Very nice when you get tired of writing out full commands. Ideally you would place this into your .bash_profile

Usage: rhost [n]

Example: rhost 33 (removes line 33 from ~/.ssh/known_hosts)

Function assumes the $HOME exists, you could alternatively use "~/.ssh/known_hosts"

Mac OSX likes a space for sed -i "$1" d

open(){ if [[ -n "$1" ]];then explorer /e, $(cygpath -mal "$PWD/$1");else explorer /e, $(cygpath -mal "$PWD");fi }
2013-07-31 01:15:14
User: lowjax

This alternative either opens the current working directory by just issuing the open function in the commandline. Or you can specify what directory you would like to open.

Example: open /cygdrive/c/Windows

Usage: open [path]

When no option is specified it will open the current working directory

=() { echo $(($*)); }
2013-05-03 04:27:07
User: xlz
Functions: echo

POSIX compliant arithmetic evaluation.

= 10*2+3

mkalias () { echo "alias $1=\"$2\"" >> ~\.bash_aliases }
2013-01-14 13:56:35
User: xr09
Functions: echo
Tags: alias function

Is used like this:

mkalias rmcache "rm -rfv app/cache/*"