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.
3

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 11

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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Unix commandline history substitution like ^foo^bar BUT for multiple replacements

#1 You invoked a command chain. #2 You globaly replace the scriptnames and execute them direct #3 The new executed command chain [# ^foo^bar] would only replace the firts match [foo] with [bar].

floating point operations in shell scripts

-l auto-selects many more digits (but you can round/truncate in your head, right) plus it loads a few math functions like sin().

Copy file content to X clipboard

(only when vim has been compiled with +clipboard)

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"

Get MX records for a domain

command is shorter, output unnecessary longer

Do some learning...

Just realized how needless the 'ls' has been... This version is also multilingual, since there is no need to grep for a special key word ("nothing"/"nichts"/"rien"/"nada"...). And it makes use of all the available horizontal space.

Inverted cowsay

It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

Rescan partitions on a SCSI device

Used this after cloning a disk with dd to make the newly written partitions show up in /dev/

Create thumbnails and a HTML page for listing them (with links to sources)

The input images are assume to have the "JPG" extension. Mogrify will overwrite any gif images with the same name! Will not work with names with spaces.

Remove all unused kernels with apt-get

TIMTOWTDI

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