Commands using c++ (12)

  • Usage: clfavs username password num_favourite_commands file_in_which_to_backup


    24
    clfavs(){ URL="http://www.commandlinefu.com";wget -O - --save-cookies c --post-data "username=$1&password=$2&submit=Let+me+in" $URL/users/signin;for i in `seq 0 25 $3`;do wget -O - --load-cookies c $URL/commands/favourites/plaintext/$i >>$4;done;rm -f c;}
    suhasgupta · 2009-09-30 16:43:08 12
  • I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: echo $'\33[H\33[2J'


    17
    for c in `seq 0 255`;do t=5;[[ $c -lt 108 ]]&&t=0;for i in `seq $t 5`;do echo -e "\e[0;48;$i;${c}m|| $i:$c `seq -s+0 $(($COLUMNS/2))|tr -d '[0-9]'`\e[0m";done;done
    AskApache · 2009-11-03 09:12:13 2
  • Requires aria2c but could just as easily wget or anything else. A great way to build up a nice font collection for Gimp without having to waste a lot of time. :-) Show Sample Output


    10
    d="www.dafont.com/alpha.php?";for c in {a..z}; do l=`curl -s "${d}lettre=${c}"|sed -n 's/.*ge=\([0-9]\{2\}\).*/\1/p'`;for((p=1;p<=l;p++));do for u in `curl -s "${d}page=${p}&lettre=${c}"|egrep -o "http\S*.com/dl/\?f=\w*"`;do aria2c "${u}";done;done;done
    lrvick · 2010-05-18 07:38:54 0
  • /lib/ld-linux.so.2 is the runtime linker/loader for ELF binaries on Linux. =(cmd) is a zsh trick to take the output for the command "inside" it and save it to a temporary file. echo -e 'blah' | gcc -x c -o /dev/stdout - pipes the C source to gcc. -x c tells gcc that it's compiling C (which is required if it's reading from a pipe). -o /dev/stdout - tells it to write the binary to standard output and read the source from standard input. because of the the =() thing, the compiled output is stashed in a tempfile, which the loader then runs and executes, and the shell tosses the tempfile away immediately after running it. Show Sample Output


    6
    /lib/ld-linux.so.2 =(echo -e '#include <stdio.h>\nint main(){printf("c one liners\\n");}' | gcc -x c -o /dev/stdout -)
    mrtheplague · 2009-02-20 06:06:29 3
  • command to decrypt: openssl enc -aes-256-cbc -d < secret.tar.enc | tar x Of course, don't forget to rm the original files ;) You may also want to look at the openssl docs for more options.


    5
    tar c folder_to_encrypt | openssl enc -aes-256-cbc -e > secret.tar.enc
    recursiverse · 2009-07-23 06:03:39 0
  • You can tell GCC to automatically select optimization commands and produce optimized code for the local machine (the one compiling the code), but you can't normally see what switches have been selected and used unless you append a "-v" and pause compilation. Show Sample Output


    5
    cc -march=native -E -v - </dev/null 2>&1 | grep cc1
    manny79 · 2009-08-21 09:47:37 3
  • Avoids creating useless directory entries in archive, and sorts files by (roughly) extension, which is likely to group similar files together for better compression. 1%-5% improvement.


    2
    find . \! -type d | rev | sort | rev | tar c --files-from=- --format=ustar | bzip2 --best > a.tar.bz2
    pornel · 2009-12-20 14:04:39 0
  • 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. Show Sample Output


    2
    box(){ c=${2-=}; l=$c$c${1//?/$c}$c$c; echo -e "$l\n$c $1 $c\n$l"; unset c l;}
    mightybs · 2010-02-26 17:14:52 0
  • Will handle pretty much all types of CSV Files. The ^M character is typed on the command line using Ctrl-V Ctrl-M and can be replaced with any character that does not appear inside the CSV. Tips for simpler CSV files: * If newlines are not placed within a csv cell then you can replace `map(repr, r)` with r Show Sample Output


    1
    python -c 'import sys,csv; c = csv.reader(sys.stdin); [sys.stdout.write("^M".join(map(repr,r))+"\n") for r in c];' <tmp/test.csv | column -s '^M' -t
    pykler · 2010-02-01 14:57:25 1
  • When you need to add another tty device that can automatically start at boot time


    0
    sudo mknod /dev/ttyS4 c 4 68
    0disse0 · 2009-09-05 09:12:44 0
  • Thanks th John_W for suggesting the fix allowing ~/ to be used when saving a directory. directions: Type in a url, it will show a preview of what the file will look like when saved, then asks if you want to save the preview and where you want to save it. Great for grabbing the latest commandlinefu commands without a full web browser or even a GUI. Requires: w3m Show Sample Output


    0
    read -p "enter url:" a ; w3m -dump $a > /dev/shm/e1q ; less /dev/shm/e1q ; read -p "save file as text (y/n)?" b ; if [ $b = "y" ] ; then read -p "enter path with filename:" c && touch $(eval echo "$c") ; mv /dev/shm/e1q $(eval echo "$c") ; fi ; echo DONE
    LinuxMan · 2010-07-13 22:36:38 2
  • It's hard to beat C. This is just slightly faster than the bc version on my machine. real 0m26.856s user 0m25.030s sys 0m0.024s Requirements: libgmp headers, gcc. Show Sample Output


    -5
    gcc -x c -o /tmp/out - -lgmp <<< '#include <stdlib.h> ... SEE SAMPLE OUTPUT FOR FULL COMMAND
    hank · 2009-09-10 02:10:46 3

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Get disk quota usage openvz using vzlist
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Viewable terminal session over network.
connect to it with any network command (including web browser - if you don't mind weird formatting) curl 127.0.0.1:9876 nc 127.0.0.1 9876

Slow down the screen output of a command
(example above is the 'ls' command with reduced output speed)

Rename files in batch

Rename all files in lower case

Find processes stuck in dreaded "D" state aka IO Wait
Lots of fun to run on nfs clients when the server or network connection is having issues

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"

This will allow you to browse web sites using "-dump" with elinks while you still are logged in
README: This require you to login on facebook with elinks without using '-dump' first time and when you have logged in you will then be able to dump all data from facebook without any advanced combos, dump is all you need for see all your friends newsfeed or whatever you wish to view in cli/terminal. Facebook is just an example, same requirements for all websites that have a login form.

colorize comm output
It just colorizes the line based on if it has 0, 1 or 2 tabs at the beginning of the line. Won't work so well if lines already begin with tabs (too bad comm doesn't have an option to substitute \t for something else). Don't forget comm needs input files to be sorted. You can use a shortcut like this with bash: comm

Create a random file of a certain, and display progress along the way.
SIZE is the number of gigabytes and the file name is at the end. Random data is generated by encrypting /dev/zero, similar to other techniques posted on here.


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