Commands by unefunge

Commands by unefunge (19)

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Backup a file with a date-time stamp

even shorter (infix) version. Show Sample Output
This is sample output - yours may be different.
```
$ buf() { cp -v $1 ${1/${1%%.*}/$f-$(date +"%Y%m%d_%H%M%S")};}
$ buf a.txt
`a.txt' -> `a-20101215_131256.txt'
$ buf a.txt.gz
`a.txt.gz' -> `a-20101215_131305.txt.gz'
```
0

buf() { cp -v $1 ${1/${1%%.*}/$f-$(date +"%Y%m%d_%H%M%S")};}

unefunge · 2010-12-15 12:16:03 0
Do one ping to a URL, I use this in a MRTG gauge graph to monitor connectivity
This is sample output - yours may be different.
2

ping -q -c 1 www.google.com|awk -F/ 'END{print $5}'

unefunge · 2010-12-15 11:01:10 1
Backup a file with a date-time stamp

"infix" version in bash (4.x+) Remove -v to make it silent. BTW: The OP forgot to use "cat" and "nmap" ;-) I had a good laugh though. Show Sample Output
This is sample output - yours may be different.
```
$ buf a.txt
`a.txt' -> `a-20101215_104638.txt'
$ buf a.txt.gz
`a.txt.gz' -> `a-20101215_104647.txt.gz'
```
0

buf() { f=${1%%.*};e=${1/$f/};cp -v $1 $f-$(date +"%Y%m%d_%H%M%S")$e;}

unefunge · 2010-12-15 09:50:04 0
Backup a file with a date-time stamp

1. you don't need to prepend the year with 20 - just use Y instead of y 2. you may want to make your function a bit more secure: buf () { cp ${1?filename not specified}{,$(date +%Y%m%d_%H%M%S)}; }
This is sample output - yours may be different.
2

buf () { cp $1{,$(date +%Y%m%d_%H%M%S)}; }

unefunge · 2010-12-14 14:02:03 0
Function to split a string into an array

Show Sample Output
This is sample output - yours may be different.
```
read -a ARR <<<'world domination now!'; echo ${ARR[2]};
now!

IFS=":" read -a ARR <<<"$PATH"; echo ${ARR[2]};
/usr/local/bin
```
10

read -a ARR <<<'world domination now!'; echo ${ARR[2]};

unefunge · 2010-12-03 16:27:03 2
Binary clock

cryptic version Show Sample Output
This is sample output - yours may be different.
```
...#
..#.
..#.
..##
```
2

read -a A <<<"8 9 5 10 6 0 3 11 7 4";B='.*.**..*....***';for C in $(date +"%H%M"|fold -w1);do echo "${B:${A[C]}:4}";done

unefunge · 2010-11-26 11:29:23 2
Binary clock

Lightweight alternative with case Show Sample Output
This is sample output - yours may be different.
```
...*
...*
.*.*
.**.
```
0

for a in $(date +"%H%M"|cut -b1,2,3,4 --output-delimiter=" ");do case "$a" in 0)echo "....";;1)echo "...*";;2)echo "..*.";;3)echo "..**";;4)echo ".*..";;5)echo ".*.*";;6)echo ".**.";;7)echo ".***";;8)echo "*...";;9)echo "*..*";;esac;done

unefunge · 2010-11-26 10:58:22 0
Monitor a file with tail with timestamps added
This is sample output - yours may be different.
3

tail -f file |xargs -IX printf "$(date -u)\t%s\n" X

unefunge · 2010-11-25 11:23:13 1
Find which service was used by which port number
This is sample output - yours may be different.
2

getent services <port_number>

unefunge · 2010-11-25 08:30:35 0
Find which service was used by which port number

I used 110 as the port number in examples for clarity. backslash+lessthan or backslash+b marks 'edge of the word'. Show Sample Output
This is sample output - yours may be different.
```
pop3            110/tcp    # Post Office Protocol - Version 3
pop3            110/udp    # Post Office Protocol - Version 3
```
0

grep '\<110/' /etc/services; grep '\b110/' /etc/services

unefunge · 2010-11-25 08:29:42 0
Binary clock

displays current time in "binary clock" format (loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/ "Decoding": 8421 .... - 1st hour digit: 0 *..* - 2nd hour digit: 9 (8+1) .*.. - 1st minutes digit: 4 *..* - 2nd minutes digit: 9 (8+1) Prompt-command version: PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"' Show Sample Output
This is sample output - yours may be different.
```
....
....
.*..
...*
```
3

echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=' ') f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"

unefunge · 2010-11-24 23:49:21 2
get function's source

no need to reinvent the wheel. Thanks to the OP for the "obsolete" hint. 'declare' may come in pretty handy on systems paranoid about "up-to-dateness" Show Sample Output
This is sample output - yours may be different.
```
$ typeset -f startx
startx () 
{ 
    test -x /usr/bin/startx || { 
        echo "No startx installed" 1>&2;
        return 1
    };
    /usr/bin/startx ${1+"$@"} 2>&1 | tee $HOME/.xsession-errors
}
```
3

typeset -f <function name>; declare -f <function name>

unefunge · 2010-11-24 15:59:42 3
Annoying PROMPT_COMMAND animation

unset PROMPT_COMMAND to disable. Show Sample Output
This is sample output - yours may be different.
```
$                                                                              @
```
2

PROMPT_COMMAND='seq $COLUMNS | xargs -IX printf "%Xs\r" @'

unefunge · 2010-11-24 14:34:21 2
Generate MD5 hash for a string
This is sample output - yours may be different.
10

md5sum <<<"test"

unefunge · 2010-11-24 12:04:41 8

Used it on daily basis, not sure if it's any better than the OPs version, tho' One advantage is - you can replace 'bash' at the end of the line with eg. cat - to check if the generated command is OK. Show Sample Output

-1

mailq |awk '/MAILER-DAEMON/{gsub("*","");printf("postsuper -d %s\n",$1)}'|bash

unefunge · 2010-11-24 11:42:54 0

Fibonacci numbers with awk

recursive version, "pure" AWK Show Sample Output
This is sample output - yours may be different.
```
0
1
1
2
3
5
8
13
21
34
55
89
144
233
377
610
987
1597
2584
4181
6765
10946
17711
28657
```
5

awk 'func f(n){return(n<2?n:f(n-1)+f(n-2))}BEGIN{while(a<24){print f(a++)}}'

unefunge · 2010-11-24 10:40:08 2
Directory bookmarks

pushd and popd are your friends, but sometimes they're just incompatible with the way one works... Two shell functions: bm bookmarkname - "bookmarks" the current directory, just 'cd $BMbookmarkname' to return to it. forget bookmarkname - unsets the 'bookmarkname' variable. It isn't mandatory, they cease to exist when the session ends. Show Sample Output
This is sample output - yours may be different.
```
$ cd /home/user/very/complicated-and-quirky/dir.ectory/name/foo
$ bm foo
$ cd /var/log/apache2
$ pwd
/var/log/apache2
$ # many commands and cd's later...
$ cd $BMf<Tab>oo # you can use bash's autocompletion mechanism
$ pwd 
/home/user/very/complicated-and-quirky/dir.ectory/name/foo
$
```
2

bm() { export BM${1?"bookmark name missing"}="$PWD" ; }; forget() { unset BM${1?"bookmark name missing"} ; }

unefunge · 2010-11-19 12:15:11 0
Generate trigonometric/log data easily
This is sample output - yours may be different.
2

echo "e("{1..8}");" | bc -l

unefunge · 2010-11-18 21:18:22 0
Bash: escape '-' character in filename
This is sample output - yours may be different.
4

mv -- -filename filename

unefunge · 2010-11-17 12:52:36 0

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check open ports without netstat or lsof

list files recursively by size

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"

Stop Flash from tracking everything you do.

Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.

Create Encrypted WordPress MySQL Backup without any DB details, just the wp-config.php

The coolest way I've found to backup a wordpress mysql database using encryption, and using local variables created directly from the wp-config.php file so that you don't have to type them- which would allow someone sniffing your terminal or viewing your shell history to see your info. I use a variation of this for my servers that have hundreds of wordpress installs and databases by using a find command for the wp-config.php file and passing that through xargs to my function.

easy C shell math calculators

allows simple C shell access to the power of bc - never could figure out how to do the same thing with Bash - that's why I use tcsh most of the time.

Short and sweet output from dig(1)

Turn off almost all of dig's output except for what you'd see in a zone file. This can also be put into ~/.digrc.

Parallel file downloading with wget

xargs can be used in this manner to download multiple files at a time, and xargs will in this case run 10 processes at a time and initiate a new one when the number running falls below 10.

How to run a command on a list of remote servers read from a file

dsh - Distributed shell, or dancer?s shell ;-) you can put your servers into /etc/dsh/machines.list than you don't have to serperate them by commata or group them in different files and only run commands for this groups dsh -M -c -a -- "apt-get update"

Function that outputs dots every second until command completes

Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes. Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!; The wait is also used here, though it may not be needed on your system. $ echo ">>> ENCRYPTING SQL BACKUP" $ gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & $ PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

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