Commands by taliver

Commands by taliver (5)

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Leap year calculation
This is sample output - yours may be different.
2

leapyear() { [ $(date -d "Dec 31, $1" +%j) == 366 ] && echo leap || echo not leap; }

taliver · 2010-03-30 20:13:56 24
Display the output of a command from the first line until the first instance of a regular expression.

Slightly simpler version of previous sed command that does the same thing. In this case, the output will stop at the command, and the entire command will be terminated as well, instead of proceeding through the whole file.
This is sample output - yours may be different.
1

command | sed '/regex/q'

taliver · 2009-12-29 14:52:41 2

Plot frequency distribution of words from files on a terminal.

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output

This is sample output - yours may be different.

$ cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

  60 .+-----+------+------+------+-------+------+------+------+------+-----++
     +      +      +      +      +       +      +      +      +      +      +
     |                                                                      |
  50 ++                                                                    ++
     |                                                                      |
     |.                                                                     |
     |.                                                                     |
  40 ++                                                                    ++
     |                                                                      |
     | ..                                                                   |
  30 ++                                                                    ++
     |   .                                                                  |
     |                                                                      |
  20 ++  ..                                                                ++
     |     ..                                                               |
     |       ..                                                             |
     |         ...                                                          |
  10 ++           ....                                                     ++
     |                ...............                                       |
     +      +      +      +      +   .......................................+
   0 ++-----+------+------+------+-------+------+------+------+------+-----++
     0      10     20     30     40      50     60     70     80     90    100

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

taliver · 2009-11-20 14:53:26 6

Write and run a quick C program

This is a quick hack to make a gcc caller. Since it runs with gcc instead of tcc, it's a bit more trustworthy as far as the final answers of things go. Show Sample Output
This is sample output - yours may be different.
```
$ cat ~/.stdin.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <utmp.h>
#include <errno.h>

int main(int argc, char *argv[]) {
  #include "/dev/tty"
  return 0;
}

$ cstdin
Ctrl-D when done.
printf("Size of an unsigned long long is %lu\n", sizeof (unsigned long long));
Size of an unsigned long long is 8
```
-3

alias cstdin='echo "Ctrl-D when done." && gcc -Wall -o ~/.stdin.exe ~/.stdin.c && ~/.stdin.exe'

taliver · 2009-11-19 16:38:51 3
Random password generating function

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60. Show Sample Output
This is sample output - yours may be different.
```
$ mkpasswd 56
AB:C[)\"=H#J:E()EY>HA6J,R741+ACL&08PC)P4Z#3R^YZ*3L0@O<<6
$ mkpasswd 9
YMO;<&.FB
```
-3

mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/$.\{'$1'\}$.*/\1/p' ;}

taliver · 2009-11-19 14:27:52 4

What's this?

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Nginx - print all optional modules before compilation

wget http://nginx.org/download/nginx-1.15.3.tar.gz && tar -xzf 1.15.3.tar.gz && cd nginx-1.15.3

create shortcut keys in bash

set history file length

set how many commands to keep in history Default is 500 Saved in /home/$USER/.bash_history Add this to /home/$USER/.bashrc HISTFILESIZE=1000000000 HISTSIZE=1000000

list block devices

Shows all block devices in a tree with descruptions of what they are.

mplayer -vo aa foo.mpg

mplayer -vo caca will give you a similar result but in color

Download Entire YouTube Channel - all of a user's videos

create the function then run 'yt-chanrip username' to download that user's entire channel. uses youtube-dl and the GData API. similar to http://www.commandlinefu.com/commands/view/3154/download-youtube-playlist

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

check open ports without netstat or lsof

Get all ip address for the host

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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