Commands using cat (514)

  • install json-to-js as a npm global package


    0
    cat data.json | json-to-js | pbcopy
    minademian · 2018-12-14 15:55:41 42
  • Plain old `unzip` won't unzip output coming from STDOUT the ZIP file format includes a directory (index) at the end of the archive. This directory says where, within the archive each file is located and thus allows for quick, random access, without reading the entire archive. This would appear to pose a problem when attempting to read a ZIP archive through a pipe, in that the index is not accessed until the very end and so individual members cannot be correctly extracted until after the file has been entirely read and is no longer available. As such it appears unsurprising that most ZIP decompressors simply fail when the archive is supplied through a pipe. The directory at the end of the archive is not the only location where file meta information is stored in the archive. In addition, individual entries also include this information in a local file header, for redundancy purposes. From the `jar` manpage: > The jar command is a general-purpose archiving and compression tool, based on ZIP and the ZLIB compression format. JAR is smart enough to know how to handle these local file headers when the index is unavailable when reading through the pipe. (Most of the explanation in this description is taken from https://serverfault.com/a/589528/314226 , though they recommend using `bsdtar`, but that is not always available on systems) Show Sample Output


    0
    cat foo.zip | jar xv
    bbbco · 2019-01-14 22:08:19 33
  • Overwrites remote file without asking! Uses HTTPS proxy that supports CONNECT. Actually uses SSH and not SFTP to upload the file.


    0
    cat myFile.json | ssh root@remoteSftpServer -o "ProxyCommand=nc.openbsd -X connect -x proxyhost:proxyport %h %p" 'cat > myFile.json'
    casueps · 2020-01-22 11:00:20 107
  • Especially good for exported ipython files Show Sample Output


    0
    grep -v '^# In' viz.txt | cat -s > out.txt
    shantanuo · 2022-06-08 04:01:11 505
  • This command works only if the line "DROP TABLE IF EXISTS" exists for all tables in the mysqldump file. It acts like a state machine.


    0
    cat db_dump.sql | awk '/DROP TABLE IF EXISTS/ { skip = $5 ~ /table1|table2/ } !skip { print $0 }' > db_dump_filtered.sql
    stf42 · 2022-10-30 16:58:57 800
  • tells you the number of lines in said file, and then tail the last 100 lines ( or how many are messed up) then u take the total amount of lines and then subract the 100 or so lines u DONT WANT, then do a head -n $new_number and then redirect it to new file.db


    -1
    cat -n $file | tail -n 100 && head -n number-of-lines-you-want-to-keep > newfile
    bbelt16ag · 2009-02-15 01:02:10 9
  • In July 2008, there was an uproar over Foxconn motherboards feeding Linux installs incorrect ACPI information (http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=869249). Foxconn has gladly corrected their mistake, but make sure it's not happening on your motherboard! After running the command, just view the 'dsdt.dsl' in any editor you like. Show Sample Output


    -1
    sudo aptitude -y install iasl && sudo cat /sys/firmware/acpi/tables/DSDT > dsdt.dat && iasl -d dsdt.dat
    brettalton · 2009-02-15 23:13:50 13
  • Be aware of using the --password argument as it will appear your password in plain text on the screen. You may use -p argument instead, it will prompt you to enter you password in hidden mode.


    -1
    cat schema.sql data.sql test_data.sql | mysql -u user --password=pass dbname
    tristan_ph · 2009-03-24 08:39:40 6
  • I'm sure almost everybody knows this by now. This command will pull the password for the admin login of any plesk machine. Show Sample Output


    -1
    cat /etc/psa/.psa.shadow
    jigglebilly · 2009-04-30 18:08:12 4
  • This is useful for displaying a portion of a FILE that contains an error at line NUMBER


    -1
    cat -n FILE | grep -C3 "^[[:blank:]]\{1,5\}NUMBER[[:blank:]]"
    lv4tech · 2009-05-17 18:19:55 8
  • VARNAMES='ID FORENAME LASTNAME ADDRESS CITY PHONE MOBILE MAIL ...' cat customer.csv | while read LINE ; do COUNT=1 for VAR in $VARNAMES ; do eval "${VAR}=`echo $LINE | /usr/bin/awk {'print $'$COUNT''}`" let COUNT=COUNT+1 done done Maybe you have a CSV-File with addresses, where you have to process each contact (one per line, write each value to own variable). Of course you can define every variable, but this way is more simple and faster (to write). VARNAMES includes the variable names. Pay attention: the number of names in VARNAMES have to be the same than in the CSV-file the fields. If the CSV is not seperated with ";", you can set the seperator after the awk-binary with -F"_" for example.


    -1
    VARNAMES='ID FORENAME LASTNAME ADDRESS CITY PHONE MOBILE MAIL' ; cat customer.csv | while read LINE ; do COUNT=1 ; for VAR in $VARNAMES ; do eval "${VAR}=`echo $LINE | /usr/bin/awk {'print $'$COUNT''}`" ; let COUNT=COUNT+1 ; done ; done
    GeckoDH · 2009-05-19 11:23:00 4
  • avoid mouse abuse and the constant struggle of balancing scroll velocity ... not to mention that burning sensation in your upper right shoulder ....


    -1
    cat large.xml | xclip
    copremesis · 2009-07-08 16:30:07 8
  • If you are downloading a big file (or even a small one) and the connection breaks or times out, use this command in order to RESUME the download where it failed, instead of having to start downloading from the beginning. This is a real win for downloading debian ISO images over a buggy DSL modem. Take the partially downloaded file and cat it into the STDIN of curl, as shown. Then use the "-C -" option followed by the URL of the file you were originally downloading. Show Sample Output


    -1
    cat file-that-failed-to-download.zip | curl -C - http://www.somewhere.com/file-I-want-to-download.zip >successfully-downloaded.zip
    linuxrawkstar · 2009-08-05 13:33:06 16

  • -1
    echo capitalize | { dd bs=1 count=1 conv=ucase 2> /dev/null; cat ;}
    twfcc · 2009-09-05 01:49:53 40
  • Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.


    -1
    for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done
    Sunng · 2009-10-12 12:49:18 5
  • Yep, is hard, but is a way more flexible using pipe.


    -1
    cat infile | while read str; do echo "$((++i)) - $str" ; done;
    glaudiston · 2009-12-09 14:05:09 3
  • Get Memeory Info


    -1
    cat /proc/meminfo
    svnlabs · 2010-01-22 16:48:03 3
  • You don't need to create an intermediate file, just pipe the output directly to tar command and use stin as file (put a dash after the f flag).


    -1
    cat 1.tar.gz 2.tar.gz | tar zxvif -
    psychopenguin · 2010-05-09 03:50:00 5
  • -r to use extended regex ^ begin line | alternative get 100 or 0-9 one or two times Show Sample Output


    -1
    cat file | sed -n -r '/^100$|^[0-9]{1,2}$/p'
    voyeg3r · 2010-05-15 19:15:56 5
  • thx Montecristo, thx hckhckhck


    -1
    cat > {filename} {your text} [^C | ^D]
    sphere64 · 2010-06-03 09:02:12 3
  • It works in every linux box Show Sample Output


    -1
    cat /proc/cpuinfo
    magicjohnson_ · 2010-09-24 09:27:58 3
  • Is a simple script for video streaming a movie


    -1
    cat video.ogg | nc -l -p 4232 & wget http://users.bshellz.net/~bazza/?nombre=name -O - & sleep 10; mplayer http://users.bshellz.net/~bazza/datos/name.ogg
    el_bazza · 2010-11-29 03:34:31 5
  • This command deletes the "newline" chars, so its output maybe unusable :)


    -1
    cat file | tr -d "\n"
    uzsolt · 2010-12-02 09:22:02 3
  • Change your drive letter as you wish. Using pv command for speed detect.First of all you must install pv command for usage. http://www.bayner.com/ kerim@bayner.com Show Sample Output


    -1
    cat /dev/sda | pv -r > /dev/null
    kerim · 2011-01-23 22:58:56 5

  • -1
    grabtweets() { curl -s -o $GT_TMP twitter.com/$1 | cat $GT_TMP | grep entry-content | sed -e :loop -e 's/<[^>]*>//g;/</N;//bloop' | sed 's/^[ \t]*//'; }
    gl101 · 2011-05-04 21:49:08 5
  • ‹ First  < 15 16 17 18 19 >  Last ›

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View online pdf documents in cli
Probably will not work very well with scanned documents.

quickly change all .html extensions on files in folder to .htm

Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Convert files from DOS line endings to UNIX line endings
Here "^M" is NOT "SHIFT+6" and "M". Type CTRL+V+M to get it instead. Its shortest and easy. And its sed!, which is available by default in all linux flavours.. no need to install extra tools like fromdos.

get a desktop notification from the terminal
tired of switching to the console to check if some command has finished yet? if notify-send does not work on your box try this one... e.g. rsync -av -e /usr/bin/lsh $HOME slowconnection.bar:/mnt/backup ; z (now fire up X, do something useful, get notified if this stuff has finished).

prevent large files from being cached in memory (backups!)
We all know... $ nice -n19 for low CPU priority.   $ ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do $ cachedel   To check the cache status of a file, do $ cachestats

Quick and Temporary Named Commands
* Add comment with # in your command * Later you can search that command on that comment with CTRL+R In the title command, you could search it later by invoking the command search tool by first typing CTRL+R and then typing "revert"

Reverse ssh
Both hosts must be running ssh and also the outside host must have a port forwarded to port 22.

Find the package that installed a command


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