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 6
  • 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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Which processes are listening on a specific port (e.g. port 80)
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bash find function
basic find implementation for systems that don't actually have find, like an android console without busybox installed.

kill a process(e.g. conky) by its name, useful when debugging conky:)

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"

sort ip by count quickly with awk from apache logs
creates associative array from apache logs, assumes "combined" log format or similar. replace awk column to suit needs. bandwidth per ip is also useful. have fun. I haven't found a more efficient way to do this as yet. sorry, FIXED TYPO: log file should obviously go after awk, which then pipes into sort.

Extract neatly a rar compressed file
It's also possible to delay the extraction (echo "unrar e ... fi" |at now+20 minutes) wich is really convenient!

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Determine MAC address of remote host when you know its IP address
arping sends ARP requests to a neighboring host. This won't work if there is an ARP subnet gateway in the middle. If there is, you'll just get the gateway's MAC address not the host's address you are really trying to get to.

Split a large file, without wasting disk space
It's common to want to split up large files and the usual method is to use split(1). If you have a 10GiB file, you'll need 10GiB of free space. Then the OS has to read 10GiB and write 10GiB (usually on the same filesystem). This takes AGES. . The command uses a set of loop block devices to create fake chunks, but without making any changes to the file. This means the file splitting is nearly instantaneous. The example creates a 1GiB file, then splits it into 16 x 64MiB chunks (/dev/loop0 .. loop15). . Note: This isn't a drop-in replacement for using split. The results are block devices. tar and zip won't do what you expect when given block devices. . These commands will work: $ hexdump /dev/loop4 . $ gzip -9 < /dev/loop6 > part6.gz . $ cat /dev/loop10 > /media/usb/part10.bin

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.


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