Commands using echo (1,545)


  • 6
    (echo "set terminal png;plot '-' u 1:2 t 'cpu' w linespoints;"; sudo vmstat 2 10 | awk 'NR > 2 {print NR, $13}') | gnuplot > plot.png
    grokskookum · 2009-09-23 16:40:13 12
  • this is helpful because dmesg is where i/o errors, etc are logged to... you will also be able to see when the system reboots or someone attaches a thumb drive, etc. don't forget to set yourself up in /etc/aliases to get roots email.


    6
    (crontab -l; echo '* * * * * dmesg -c'; ) | crontab -
    grokskookum · 2009-09-30 18:13:38 3
  • Changing newline to spaces using just echo Show Sample Output


    6
    echo $(</tmp/foo)
    tatsu · 2009-10-01 12:43:20 4
  • This is how I list the crontab for all the users on a given system that actually have a crontab. You could wrap it with a function block and place it in your .profile or .bashrc for quick access. There's prolly a simpler way to do this. Discuss. Show Sample Output


    6
    for USER in `cut -d ":" -f1 </etc/passwd`; do crontab -u ${USER} -l 1>/dev/null 2>&1; if [ ! ${?} -ne 0 ]; then echo -en "--- crontab for ${USER} ---\n$(crontab -u ${USER} -l)\n"; fi; done
    tharant · 2009-10-07 20:51:01 4
  • bash2 : for X in $(seq 1 5); do printf "%03g " "$X";done bash3 : for X in {1..5}; do printf "%03g " "$X";done bash4 : echo {001..5} Show Sample Output


    6
    echo {001..5}
    nanard06 · 2009-10-29 16:25:44 11

  • 6
    echo .*
    unixmonkey7109 · 2009-11-21 04:07:28 5
  • @putnamhill, no need if statement in that case. && is a AND and || is a OR


    6
    nc -zw2 www.example.com 80 && echo open
    sputnick · 2009-12-07 21:35:25 11

  • 6
    for k in `git branch|sed s/^..//`;do echo -e `git log -1 --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" "$k"`\\t"$k";done|sort
    unixmonkey7740 · 2010-01-06 18:35:29 6
  • I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';} Show Sample Output


    6
    spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://www.google.com/tbproxy/spell|sed -n '/s="[0-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}'|tee >(grep -Eq '.*'||echo -e "OK");}
    eightmillion · 2010-02-17 08:20:48 17
  • First argument: string to put a box around. Second argument: character to use for box (default is '=') Same as command #4948, but shorter, and without the utility function. Show Sample Output


    6
    box() { t="$1xxxx";c=${2:-=}; echo ${t//?/$c}; echo "$c $1 $c"; echo ${t//?/$c}; }
    bartonski · 2010-02-26 13:17:12 7
  • Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant. Show Sample Output


    6
    TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"
    d34dh0r53 · 2010-02-26 20:29:45 8
  • 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


    6
    echo 'ServerAliveInterval 60' >> /etc/ssh/ssh_config
    rpavlick · 2010-03-31 09:22:54 7
  • 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) Show Sample Output


    6
    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;}
    AskApache · 2010-04-21 00:40:37 30

  • 6
    cat list|while read lines;do echo "USER admin">ftp;echo "PASS $lines">>ftp;echo "QUIT">>ftp;nc 192.168.77.128 21 <ftp>ftp2;echo "trying: $lines";cat ftp2|grep "230">/dev/null;[ "$?" -eq "0" ]&& echo "pass: $lines" && break;done
    FuRt3X · 2010-05-02 07:37:22 30
  • Generates a random 8-character password that can be typed using only the left hand on a QWERTY keyboard. Useful to avoid taking your hand off of the mouse, especially if your username is left-handed. Change the 8 to your length of choice, add or remove characters from the list based on your preferences or kezboard layout, etc.


    6
    </dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8; echo ""
    TexasDex · 2010-06-17 19:30:36 3
  • Streams youtube video with v=ID directly into the mplayer. If exists, it uses the HD-quality stream. If you don't want to watch it in HD-quality, you can use the shorter form: ID=52DnUo6wJto; mplayer -fs $(echo "http://youtube.com/get_video.php?&video_id=$ID$(wget -qO - 'http://youtube.com/watch?v='$ID | perl -ne 'print $1."&asv=" if /^.*(&t=.*?)&.*$/')")


    6
    ID=52DnUo6wJto;mplayer -fs $(echo "http://youtube.com/get_video.php?&video_id=$ID$(wget -qO - 'http://youtube.com/watch?v='$ID | perl -ne 'print $1."&asv=" if /^.*(&t=.*?)&.*$/; print "&fmt=".$1 if /^.*&fmt_map=(22).*$/')")
    lslah · 2010-09-17 17:06:55 4
  • Pipe Viewer allows you to monitor the progress of a data transfer or command, or to show the time elapsed, among other things. In this use, it limits the transfer rate of the echo command to 10 bytes per second, making your text appear to be typed out in real time as in Hollywood movies. Fun!


    6
    echo "text to be displayed" | pv -qL 10
    journalsquared · 2010-10-21 20:51:51 7
  • This is useful when watching a log file that does not contain timestamps itself. If the file already has content when starting the command, the first lines will have the "wrong" timestamp when the command was started and not when the lines were originally written.


    6
    tail -f file | while read line; do echo -n $(date -u -Ins); echo -e "\t$line"; done
    hfs · 2010-11-19 10:01:57 8

  • 6
    echo "You can have a bit more realistic typing with some shell magic." | pv -qL $[10+(-2 + RANDOM%5)]
    nkoehring · 2011-02-16 01:40:35 8
  • You can choose these mirror servers to get gpg keys, if the official one ever goes offline keyserver.ubuntu.com pool.sks-keyservers.net subkeys.pgp.net pgp.mit.edu keys.nayr.net keys.gnupg.net wwwkeys.en.pgp.net #(replace with your country code fr, en, de,etc)


    6
    sudo apt-get update 2> /tmp/keymissing; for key in $(grep "NO_PUBKEY" /tmp/keymissing |sed "s/.*NO_PUBKEY //"); do echo -e "\nProcessing key: $key"; gpg --keyserver pool.sks-keyservers.net --recv $key && gpg --export --armor $key |sudo apt-key add -; done
    Bonster · 2011-03-30 08:18:54 8
  • useful to use after with the --load-cookies option of wget


    6
    echo ".mode tabs select host, case when host glob '.*' then 'TRUE' else 'FALSE' end, path, case when isSecure then 'TRUE' else 'FALSE' end, expiry, name, value from moz_cookies;" | sqlite3 ~/.mozilla/firefox/*.default/cookies.sqlite
    euridice · 2011-08-15 14:49:47 10
  • Usage: upper [STRING]... Show Sample Output


    6
    upper() { echo ${@^^}; }
    sharfah · 2011-10-07 11:38:44 5
  • This puts a clock in the top right of the terminal. This version doesn't use tput, but uses escape codes


    6
    while true; do echo -ne "\e[s\e[0;$((COLUMNS-27))H$(date)\e[u"; sleep 1; done &
    SQUIIDUX · 2012-11-11 02:16:21 12
  • This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables. Show Sample Output


    6
    dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
    rodolfoap · 2013-01-31 01:38:30 13
  • (Please see sample output for usage) Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.: myscript --> myscript.crypt You can execute myscript.crypt only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Sorry for the chmod on parentheses, I dont like "-" at the end. Thanks flatcap for the subshell abbreviation to /dev/null Show Sample Output


    6
    read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
    rodolfoap · 2013-03-10 08:59:45 13
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Search recursively to find a word or phrase in certain file types, such as C code
I have a bash alias for this command line and find it useful for searching C code for error messages. The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching. This find command find all .c and .h files

List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

Convert Squid unixtime logs in human-readable ones
On-the-fly conversion of Unix Time to human-readable in Squid's access.log

Recursively remove all empty directories

Run a command multiple times with different subcommands
it's nice to be able to use the command `ls program.{h,c,cpp}`. This expands to `ls program.h program.c program.cpp`. Note: This is a text expansion, not a shell wildcard type expansion that looks at matching file names to calculate the expansion. More details at http://www.linuxjournal.com/content/bash-brace-expansion I often run multiple commands (like apt-get) one after the other with different subcommands. Just for fun this wraps the whole thing into a single line that uses brace expansion.

list block devices
Shows all block devices in a tree with descruptions of what they are.

sed /pat/!d without using sed (no RE; limited to shell patterns aka globbing)
POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

List all databases in Postgres and their (byte/human) sizes, ordering by byte size descending
Get a listing of all of your databases in Postgres and their sizes, ordering by the largest size first. Requires that you give the -d parameter a valid database name that you can connect to.

print a python-script (or any other code) with syntax-highlighting and no loss of indentation


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