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Commands using echo from sorted by
Terminal - Commands using echo - 1,331 results
if grep -q "$b" <<<$a; then echo "'$b' was found in '$a'"; fi
shmore(){ local l L M="`echo;tput setab 4&&tput setaf 7` --- SHMore --- `tput sgr0`";L=2;while read l;do echo "${l}";((L++));[[ "$L" == "${LINES:-80}" ]]&&{ L=2;read -p"$M" -u1;echo;};done;}
2010-04-21 00:40:37
User: AskApache
Functions: echo read
6
SH
cat mod_log_config.c | shmore

or

shmore < mod_log_config.c

Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable.

What I wanted was a "more" pager that was basically the same as running:

cat file

Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output.

After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so

This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work.

One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the

tput setab 4; tput setaf 7

command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text.

This is one of hundreds of functions I have in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html">.bash_profile at http://www.askapache.com/">AskApache.com, but actually won't be included till the next update.

If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

true || false && echo true || echo false
2010-04-20 09:17:08
User: Sizeof
Functions: echo false true
Tags: Linux UNIX
1

You can do some boolean logic like

A or B then C else D using

or : ||

and : &&

So you can do some :

# false || false && echo true || echo false

false

# true || false && echo true || echo false

true

# false || true && echo true || echo false

true

# true || true && echo true || echo false

true

and so on ...

I use it like :

(ssh example.com 'test something') || $(ssh example.net 'test something') && echo ok || echo ko
echo $ascii | perl -ne 'printf "%x", ord for split //'
echo $ascii | perl -ne 'printf ("%x", ord($1)) while(/(.)/g); print "\n";'
echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'
echo 'obase=16; C+F' | bc
2010-04-14 20:35:31
User: rkulla
Functions: echo
Tags: hex bc math asm
4

To do hex to binary: echo 'ibase=16; obase=2; 16*16' | bc # prints: 111100100

To do 16*16 from decimal to hex: echo 'ibase=10; obase=16; 16*16' | bc # prints: 100

You get the idea... Alternatively, run bc in interactive mode (see man page)

[ -n "$SSH_CLIENT" ] && export DISPLAY=$(echo $SSH_CLIENT | awk '{ print $1 }'):0.0
2010-04-14 08:19:37
User: GouNiNi
Functions: awk echo export
0

In some case, you need to use remote gui on servers or simple machines and it's boring to see "cannot open display on ..." if you forgot to export your display. Juste add this line in .bashrc on remote machine. Dont forget to allow remote client on your local X server :

xhost +
printf -v row "%${COLUMNS}s"; echo ${row// /#}
2010-04-13 21:56:46
User: dennisw
Functions: echo printf
Tags: tr tput printf
4

Pure Bash

This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr.

printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#}

The only disadvantage to either one is that they create a variable.

if cat /proc/cpuinfo | grep " lm " &> /dev/null; then echo "Got 64bit" ; fi
2010-04-10 15:31:58
User: xeor
Functions: cat echo grep
Tags: cpuinfo
4

Check if you have 64bit by looking for "lm" in cpuinfo. lm stands for "long mem". This can also be used without being root.

alias head='head -n $((${LINES:-`tput lines 2>/dev/null||echo -n 12`} - 2))'
26

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 )

275MB/748MB

[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.

prefix="10.0.0" && for i in `seq 25`; do ping -c 1 $prefix.$i &> /dev/null && echo "Answer from: $prefix.$i" ; done
2010-04-07 17:17:21
User: xeor
Functions: echo ping
Tags: ping
-2

Not really an easier solution. But an example using && for (if last command returned 0). You can use || for (if last command returned other than 0)..

for i in `find /home/ -maxdepth 1 -type d`; do echo -n $i " ";find $i|wc -l; done
2010-04-07 05:33:49
User: shantanuo
Functions: echo wc
1

Find the number of files from each folder

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
-1

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
-3

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

du -cks * | sort -rn | while read size fname; do for unit in k M G T P E Z Y; do if [ $size -lt 1024 ]; then echo -e "${size}${unit}\t${fname}"; break; fi; size=$((size/1024)); done; done
echo "scale=6;2048 / 2.345" | bc
echo Your_Chinese_Char | uniconv -encode Chinese-WB
2010-04-05 10:57:42
User: eastwind
Functions: echo
1

This CLI requiere the uniconv package that is provided with the yudit unicode editor .

The wubi86 is a way to type chinese far quicker than pinyin .

More infor on wikipedia : http://en.wikipedia.org/wiki/Wubizixing , http://www.yale.edu/chinesemac/wubi/xing.html

echo 'ServerAliveInterval 60' >> /etc/ssh/ssh_config
2010-03-31 09:22:54
User: rpavlick
Functions: echo
Tags: ssh timeout
6

ssh_config is the system-wide configuration file for ssh.

For per-user configuration, which allows for different settings for each host:

echo 'ServerAliveInterval 60' >> ~/.ssh/ssh_config

On OSX:

echo 'ServerAliveInterval 60' >> ~/.ssh/config

or

echo 'ServerAliveInterval 60' >> ~/etc/ssh_config
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
-2

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 "$year isn't leap year";
count="1" ; while true ; do read next ; if [[ "$next" = "$last" ]] ; then count=$(($count+1)) ; echo "$count" ; else count="1" ; echo $count ; fi ; last="$next" ; done
2010-03-30 04:02:29
User: dabom
Functions: echo read true
Tags: bash read Game
8

Really bored during class so I made this...

Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line...

My record was 5 lines of the same length.

It's best if you do it one handed with your pointer on period and ring on enter.

gorecord() { if [ $# != 1 ]; then echo 'gorecord video.mp4' return fi ffmpeg -f x11grab -s <resolution> -r 25 -i :0.0 -sameq -vcodec mpeg4 "$1" }
2010-03-29 20:21:35
User: meathive
Functions: echo return
3
gorecord foo.mp4

I've tried all of the screen recorders available for Linux and this is easily the best. xvidcap segfaults; VNC is too much hassle. There are alternatives of this command already here that I am just too lazy to reply to. Messing with the frames per second option, -r, 25 seems to be the best. Any lower and the video will look like a flipbook, if it records at all - -r 10 won't - any faster is the same, oddly enough.

Edit: CLF doesn't like my long command to add audio, so here it is in the description.

goaddaudio() { if [ $# != 3 ]; then echo 'goaddaudio < audio > < src video > < dst video >' return fi f=goaddaudio$RANDOM ffmpeg -i "$2" &> $f d=$( grep Duration $f | awk '{print $2}' | tr -d ',' ) && rm $f && ffmpeg -i "$1" -i "$2" -r 25 -ab 192k -ar 44100 -sameq -t $d "$3" }
ls -d $(echo ${PATH//:/ }) > /dev/null