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 36
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 3

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 7

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 4
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 5

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List .log files open by a pid

Uses lsof to display the full path of ".log" files opened by a specified PID.

Lists the supported memory types and how much your board can support.

generate iso

Reset terminal that has been buggered by binary input or similar

Find default gateway

mail with attachment

An easy one but nice to keep in mind.

list block devices

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

Getting the last argument from the previous command

Search gpg keys from commandline

Select and Edit a File in the Current Directory

This command displays a simple menu of file names in the current directory. After the user made a choice, the command invokes the default editor to edit that file. * Without the break statement, the select command will loop forever * Setting the PS3 prompt is optional * If the user types an invalid choice (such as the letter q), then the variable $f will become an empty string. * For more information, look up the bash's select command

Stay in the loop…

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