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Commands tagged echo from sorted by
Terminal - Commands tagged echo - 80 results
echo "your text" > filename
alias head='head -n $((${LINES:-`tput lines 2>/dev/null||echo -n 12`} - 2))'

Run the alias command, then issue

ps aux | head

and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand.

${LINES:-`tput lines 2>/dev/null||echo -n 12`}

Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the deafault of 12 (-2 = 10).

The default for HEAD is to output the first 10 lines, this alias changes the default to output the first x lines instead, where x is the number of lines currently displayed on your terminal - 2. The -2 is there so that the top line displayed is the command you ran that used HEAD, ie the prompt.

Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux-unix/bash-power-prompt.html )


[7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~

In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

date +%A | cut -c $(( $(date +%A | wc -c) - 1 ))
2010-04-07 00:23:15
User: DaveQB
Functions: cut date wc
Tags: bash echo cut date wc

A command to find out what the day ends in. Can be edited slightly to find out what "any" output ends in.

NB: I haven't tested with weird and wonderful output.

function ends_in_y() { case $(date +%A) in *y ) true ;; * ) false ;; esac } ; ends_in_y && echo ok
2010-04-06 22:18:52
Functions: date echo false true

The shell has perfectly adequate pattern matching for simple expressions.

function ends_in_y() { if [ `date +%A | sed -e 's/\(^.*\)\(.$\)/\2/'` == "y" ]; then echo 1; else echo 0; fi }
2010-04-06 20:14:34
User: allrightname
Functions: echo sed

For those days when you need to know if something is happening because the day ends in "y".

leapyear() { [ $(date -d "Dec 31, $1" +%j) == 366 ] && echo leap || echo not leap; }
leapyear() { if [ $[$1 % 4] -eq 0 ] && [ $[$1 % 100] -ne 0 ] || [ $[$1 % 400] -eq 0 ]; then echo $1' is a leap year!'; else echo $1' is not a leap year.'; fi; }
2010-03-30 17:19:20
User: kaedenn
Functions: echo
Tags: echo test

Tested on bash, and follows all the rules about leap years.

year=2010; math=`echo "$year%4" | bc`; [ ! -z $year ] && [ $math -eq 0 ] && echo "$year is leap year!" || echo "$year isn't leap year";
echo "ulimit `ulimit -a|sed -e 's/^.*\([a-z]\))\(.*\)$/-\1\2/'|tr "\n" ' '`"
2010-03-12 06:46:54
User: AskApache
Functions: echo

It is helpful to know the current limits placed on your account, and using this shortcut is a quick way to figuring out which values to change for optimization or security.

Alias is:

alias ulimith="command ulimit -a|sed 's/^.*\([a-z]\))\(.*\)$/-\1\2/;s/^/ulimit /'|tr '\n' ' ';echo"

Here's the result of this command:

ulimit -c 0 -d unlimited -e 0 -f unlimited -i 155648 -l 32 -m unlimited -n 8192 -p 8 -q 819200 -r 0 -s 10240 -t unlimited -u unlimited -v unlimited -x unlimited ulimit -a

core file size (blocks, -c) 0

data seg size (kbytes, -d) unlimited

scheduling priority (-e) 0

file size (blocks, -f) unlimited

pending signals (-i) 155648

max locked memory (kbytes, -l) 32

max memory size (kbytes, -m) unlimited

open files (-n) 8192

pipe size (512 bytes, -p) 8

POSIX message queues (bytes, -q) 819200

real-time priority (-r) 0

stack size (kbytes, -s) 10240

cpu time (seconds, -t) unlimited

max user processes (-u) unlimited

virtual memory (kbytes, -v) unlimited

file locks (-x) unlimited

echo "message" | smbclient -M NAME_OF_THE_COMPUTER
2010-02-28 21:10:46
User: mvrilo
Functions: echo

It will only work if the service NETSEND in the Windows machine is enabled.

box(){ c=${2-=}; l=$c$c${1//?/$c}$c$c; echo -e "$l\n$c $1 $c\n$l"; unset c l;}
2010-02-26 17:14:52
User: mightybs
Functions: c++ echo unset
Tags: bash echo

First argument: string to put a box around.

Second argument: character to use for box (default is '=')

Same as command #4962, cleaned up, shortened, and more efficient. Now a ' * ' can be used as the box character, and the variables get unset so they don't mess with anything else you might have.

They marked c++ as a function for this command, but I'm not sure why. Must be a bug.

while true; do echo -ne "$(date)\r"; sleep 1; done
2009-11-17 22:45:37
User: polaco
Functions: echo sleep

The above code is just an example of printing on the same line, hit Ctrl + C to stop

When using echo -ne "something\r", echo will:

- print "something"

- dont print a new line (-n)

- interpret \r as carriage return, going back to the start of the line (-e)

Remember to print some white spaces after the output if your command will print lines of different sizes, mainly if one line will be smaller than the previous

Edit from reading comments: You can achieve the same effect using printf (more standardized than echo): while true; do printf "%-80s\r" "$(date)"; sleep 1; done

seq 10 |xargs -n1 echo Printing line
2009-10-15 11:05:35
User: Waldirio
Functions: echo seq xargs
Tags: echo xargs seq

Nice command to create a list, you can create too with for command, but this is so faster.

for each in `cut -d " " -f 1 inputfile.txt`; do echo "select * from table where id = \"$each\";"; done
2009-09-23 13:29:16
User: hfs
Functions: echo
Tags: echo cut for-each

I never can remember the syntax of awk. You can give a different -d option to cut to separate by e.g. commas. Also this allows to do more things with the generated SQL, e.g. to redirect it into different files.

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

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.

for p in ${PATH//:/ }; do [[ -d $p && -x $p ]] && echo $p; done
2009-09-19 06:43:57
User: AskApache
Functions: echo

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

echo src::${PATH} | awk 'BEGIN{pwd=ENVIRON["PWD"];RS=":";FS="\n"}!$1{$1=pwd}$1!~/^\//{$1=pwd"/"$1}{print $1}'
2009-09-09 04:03:46
User: arcege
Functions: awk echo
Tags: awk echo PATH

Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts.

echo $PATH | tr \: \\n
2009-09-09 02:10:04
User: crk
Functions: echo tr
Tags: bash echo tr PATH

This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

du -a --max-depth=1 | sort -n | cut -d/ -f2 | sed '$d' | while read i; do if [ -f $i ]; then du -h "$i"; else echo "$(du -h --max-depth=0 "$i")/"; fi; done
2009-09-03 20:43:43
User: nickwe
Functions: cut du echo read sed sort

Based on the MrMerry one, just add some visuals to differentiate files and directories

find . -maxdepth 1 -type d|xargs du -a --max-depth=0|sort -rn|cut -d/ -f2|sed '1d'|while read i;do echo "$(du -h --max-depth=0 "$i")/";done;find . -maxdepth 1 -type f|xargs du -a|sort -rn|cut -d/ -f2|sed '$d'|while read i;do du -h "$i";done
2009-09-03 20:33:21
User: nickwe
Functions: cut du echo find read sed sort xargs

Based on the MrMerry one, just add some visuals and sort directory and files

echo init 0 | at now + 2 hours
echo $((`eix --only-names -I | wc -l` * 100 / `eix --only-names | wc -l`))%
echo $( du -sm /var/log/* | cut -f 1 ) | sed 's/ /+/g'
2009-07-31 21:42:53
User: flux
Functions: cut du echo sed
Tags: echo bc

When you've got a list of numbers each on its row, the ECHO command puts them on a simple line, separated by space. You can then substitute the spaces with an operator. Finally, pipe it to the BC program.

(Command too long..See sample Output..)
2009-06-14 20:34:37
User: mohan43u
Tags: bash sed echo tr od

curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).