Commands using c++ (12)

  • backup all your commandlinefu.com favourites to a plaintext file

    Usage: clfavs username password num_favourite_commands file_in_which_to_backup


    25
    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 7
  • Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X

    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 1
  • Fetch every font from dafont.com to current folder

    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
  • C one-liners

    /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
  • Encrypted archive with openssl and tar

    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
  • Show GCC-generated optimization commands when using the "-march=native" or "-mtune=native" switches for compilation.

    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 2
  • Slightly better compressed archives

    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
  • a function to create a box of '=' characters around a given string.

    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
  • Pretty Print a simple csv in the command line

    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
  • Add another tty device using mknod command

    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
  • Get a url, preview it, and save as text - with prompts

    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
  • The 1 millionth fibonacci number

    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 all IPs via ifconfig
and, a lot uglier, with sed: $ ifconfig | sed -n '/inet addr:/s/[^:]\+:\(\S\+\).*/\1/p' Edit: Wanted to be shorter than the perl version. Still think that the perl version is the best..

Using ASCII Art output on MPlayer
Not so useful. Just a cool feature.

auto terminal title change
above line in .bash_profile will give you window title in putty or terminal client when you login to your remote server

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.

Installing debian on fedora (chrooted)

mercurial close branch

Check your bash shell for vulnerability to the ShellShock exploit
If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/

Battery real life energy vs predicted remaining plotted
This time I added a print to reemaining energy, every minute, time stamped. The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end.

List only the directories
This command would be useful when it is desirable to list only the directories. 'egrep' chooses only the lines that begin with 'd'.

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"

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