Commands using echo (1,545)


  • -2
    echo "12345,12346" |sed -e's/ //'|tr "," "\n"| while read line; do echo -n $line" "; svn log -vr $line https://url/to/svn/repository/|grep "/"|head -1|cut -d"/" -f2; done
    psytek · 2009-04-15 15:21:20 4
  • You've opened a terminal window and you've connected off to a remote host that didn't pick up your terminal size, and all your curses and paging apps are screwed up as a result. You need to quickly determine how many lines are in your current terminal view (to feed into "stty rows X"). Show Sample Output


    -2
    _llines=100; while [ $_llines -gt 1 ]; do echo $_llines; _llines=$(($_llines-1)); done
    romulusnr · 2009-04-29 00:19:45 7
  • get desired info from machine and pipe it txt file. Show Sample Output


    -2
    echo "-------------" >> nicinfo.txt; echo "computer name x" >> nicinfo.txt; ifconfig | grep status >> nicinfo.txt; ifconfig | grep inet >> nicinfo.txt; ifconfig | grep ether >> nicinfo.txt; hostinfo | grep type >> nicinfo.txt;
    miccaman · 2009-06-25 12:32:37 31

  • -2
    wget http://checkip.dyndns.org && clear && echo && echo My IP && egrep -o '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}' index.html && echo && rm index.html
    onkelchentobi · 2009-08-07 21:21:59 4

  • -2
    echo $PATH|awk -F: ' { for (i=1; i <= NF; i++) print $i }'
    nitins · 2009-08-12 07:56:56 4
  • Ummmm.. Saw that gem on some dead-head hippies VW bus at phish this summer.. It's actually one of my favorite ways of using bash, very clean. It shows what you can do with the cool advanced features like job control, redirection, combining commands that don't wait for each other, and the thing I like the most is the use of the ( ) to make this process heirarchy below, which comes in very handy when using fifos for adding optimization to your scripts or commands with similar acrobatics. F UID PID PPID WCHAN RSS PSR CMD 1 gplovr 30667 1 wait 1324 1 -bash 0 gplovr 30672 30667 - 516 3 \_ sleep 3 1 gplovr 30669 1 wait 1324 1 -bash 0 gplovr 30673 30669 - 516 0 \_ sleep 5 1 gplovr 30671 1 wait 1324 1 -bash 0 gplovr 30674 30671 - 516 1 \_ sleep 7 Show Sample Output


    -2
    S=$SSH_TTY && (sleep 3 && echo -n 'Peace... '>$S & ) && (sleep 5 && echo -n 'Love... '>$S & ) && (sleep 7 && echo 'and Intergalactic Happiness!'>$S & )
    AskApache · 2009-08-19 07:57:16 7
  • Enable 'sleep' function in Windows environment where this does not exist, although not exact in time. (there is a delay for each ping) This is a simple way to separate commands with a time-period. Show Sample Output


    -2
    echo sleep() begins: %TIME% && FOR /l %a IN (10,-1,1) do (ECHO 1 >NUL %as&ping -n 2 -w 1 127.0.0.1>NUL) && echo sleep() end: %TIME%
    pfredrik · 2009-08-19 13:43:09 3
  • If you need to ssh into a computer on the local network but you're unsure of the ip to use, then ping them and see if you get a response. If you do, print out the address you got it from. Adjust the range to suit your network.


    -2
    for i in 192.168.1.{61..71};do ping -c 1 $i &> /dev/null && echo $i;fi;done
    AlecSchueler · 2009-08-26 06:04:24 11
  • 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. Show Sample Output


    -2
    echo src::${PATH} | awk 'BEGIN{pwd=ENVIRON["PWD"];RS=":";FS="\n"}!$1{$1=pwd}$1!~/^\//{$1=pwd"/"$1}{print $1}'
    arcege · 2009-09-09 04:03:46 3
  • another replacement for cat.


    -2
    echo "$(</etc/issue)"
    mobidyc · 2009-09-14 09:44:35 34
  • regex to match an ip Show Sample Output


    -2
    echo "123.32.12.134" | grep -P '([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])'
    KeePon · 2009-09-17 12:17:32 5

  • -2
    n=$RANDOM$RANDOM$RANDOM; let "n %= 10000000000"; echo $n
    alset · 2009-10-15 05:10:00 4
  • This script will list all the files in the tarballs present on any folder or subfolder of the provided path. The while loop is for echoing the file name of the tarball before listing the files, so the tarball can be identified


    -2
    find <path> -name "*.tgz" -or -name "*.tar.gz" | while read file; do echo "$file: "; tar -tzf $file; done
    polaco · 2009-11-10 20:39:04 36
  • If you gzip an empty file it becomes 20 bytes. Some backup checks i do check to see if the file is greater than zero size (-s flag) but this is no good here. Im sure someone has a better check than me for this? No check to see if file exists before checking it's size.


    -2
    BACKUP_FILE_SIZE=`eval ls -l ${BACKUP_FILE} | awk {'print $5'}`; if [ $BACKUP_FILE_SIZE -le 20 ]; then echo "its empty"; else echo "its not empty"; fi
    Redrocket · 2009-12-29 08:34:37 3
  • CHANGELOG Version 1.1 removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } BUG FIX: Folders with spaces Version 1.0 removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } BUG FIX: Hidden directories (.dotdirectory) Version 0.9 rmdir () { echo "You are about to delete the current directory $PWD. Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; } Removes current directory with recursive and force flags plus basic human check. When prompted type yes 1. [user@host ~]$ ls foo bar 2. [user@host ~]$ cd foo 3. [user@host foo]$ removedir 4. yes 5. rm -Rf foo/ 6. [user@host ~]$ 7. [user@host ~]$ ls bar Show Sample Output


    -2
    removedir () { echo "Deleting the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
    oshazard · 2010-01-17 11:34:38 31
  • Outputs multiple whois from a plain text file.


    -2
    for domain in `cat list_of_domains.txt`; do echo $domain; whois $domain >> output.txt; done
    pathcl · 2010-02-15 17:13:45 7
  • You don't want the -ar parameters in this case. The man page for BASH_BUILTINS(1) states: "-a option means to remove or mark all jobs" and "-r option without a jobspec argument restricts operation to running jobs" In this case we are supplying the process id of the job to disown so neither of these should be used.


    -2
    echo "Starting Daemon"; ( while :; do sleep 15; echo "I am still running =]"; done ) & disown -h $!
    daleki · 2010-02-23 19:17:05 3
  • find all files in cur dir add to url and append to file


    -2
    find . type f -exec echo http://exg.com/{} \; > file
    unixmonkey8504 · 2010-03-02 14:18:01 3
  • Tested on bash, and follows all the rules about leap years. Show Sample Output


    -2
    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; }
    kaedenn · 2010-03-30 17:19:20 4
  • 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).. Show Sample Output


    -2
    prefix="10.0.0" && for i in `seq 25`; do ping -c 1 $prefix.$i &> /dev/null && echo "Answer from: $prefix.$i" ; done
    xeor · 2010-04-07 17:17:21 4
  • Some servers don't have ssh-copy-id, this works in those cases. It will ask for the destination server, this can be IP, hostname, or user@hostname if different from current user. Ssh keygen will let you know if a pubkey already exists on your system and you can opt to not overwrite it.


    -2
    echo 'Host or User@Host?:'; read newserver && ssh-keygen -N "" -t rsa -f ~/.ssh/id_rsa ; ssh $newserver cat <~/.ssh/id_rsa.pub ">>" ~/.ssh/authorized_keys ; ssh $newserver
    alf · 2010-05-07 06:24:53 4
  • Currently Facebook has updated their headers to display 127.0.0.1 but if you have saved e-mails from messages and FB related mail you can still reveal the IP. :) Tested on Mac OS X 10.6.3 Show Sample Output


    -2
    echo "X-Facebook: from zuckmail ([MTI3LjAuMC4x])" | cut -d \[ -f 2 | cut -d \] -f 1 | openssl base64 -d
    IsraelTorres · 2010-05-09 00:46:28 4
  • simple bash one liner to pass multiple arguments to command one by one. optional yes/no pipe at beginning of command Show Sample Output


    -2
    yes|for x in one two three; do echo result - $x; done
    Panikos · 2010-06-01 14:49:29 3
  • Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.


    -2
    IFS=`echo -en "\n\b"`; for i in $(curl http://feeds.digg.com/digg/container/technology/popular.rss | grep '<title>' | sed -e 's#<[^>]*>##g' | tail -n10); do echo $i; echo $i | sed 's/^/Did you hear about /g' | say; sleep 30; done
    echosedawk · 2010-06-07 22:16:19 4

  • -2
    for i in 192.168.1.{1..254} ; do if ping -c1 -w1 $i &>/dev/null; then echo $i alive; fi; done
    wiburg · 2010-06-12 18:38:36 3
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Generate MD5 hash for a string

Use /dev/full to test language I/O-failsafety
The Linux /dev/full file simulates a "disk full" condition, and can be used to verify how a program handles this situation. In particular, several programming language implementations do not print error diagnostics (nor exit with error status) when I/O errors like this occur, unless the programmer has taken additional steps. That is, simple code in these languages does not fail safely. In addition to Perl, C, C++, Tcl, and Lua (for some functions) also appear not to fail safely.

Killing processes with your mouse in an infinite loop
Useful for quickly cleaning your Desktop. Nice joke if launched at startup.

list file descriptors opened by a process
Useful for examining hostile processes (backdoors,proxies)

Group OR'd commands where you expect only one to work
Something to stuff in an alias when you are working in multiple environments. The double-pipe OR will fall through until one of the commands succeeds, and the rest won't be executed. Any STDERR will fall out, but the STDOUT from the correct command will bubble out of the parenthesis to the less command, or some other command you specify.

Show a curses based menu selector
Not so much handy by itself, but very nice in shell scripts. This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like: "one" "two" "three" "four" "etc" For those who prefer bash expansion over gratuitious typing: $ whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} ) Things to note: The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time. If the status is 1, it will be selected by default. anything else, will be deselected.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Exiftool adjust Date & Time of pictures
Change the original date set by camera : Create Date : 2020:08:21 13:26:24.63 //Operating System: Date Created (ie: sdcard) Date/Time Original : 2020:08:21 13:26:24.63 // Set by camrea when you point and click for photo Modify Date : 2020:08:21 13:26:24.63 //Operating System: Modified (ie: sdcard) Exif argument examples are : exiftool.exe ā€œ-DateTimeOriginal+=0:0:0 5:30:0ā€ filename.jpg (add 5 hours and 30 minutes to the Exif Date/Time Original) exiftool.exe" "-modifydate-=0:0:0 0:25:0" filename.jpg (reduce the Exif Modify Date to 25 minutes) exiftool.exe ā€œ-AllDates+=Y:M:D h:m:sā€ filename.jpg (Change all exif date values to Y:M:D h:m:s)

Get a free shell account on a community server
Bash process substitution which curls the website 'hashbang.sh' and executes the shell script embedded in the page. This is obviously not the most secure way to run something like this, and we will scold you if you try. The smarter way would be: Download locally over SSL > curl https://hashbang.sh >> hashbang.sh Verify integrty with GPG (If available) > gpg --recv-keys 0xD2C4C74D8FAA96F5 > gpg --verify hashbang.sh Inspect source code > less hashbang.sh Run > chmod +x hashbang.sh > ./hashbang.sh


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