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 4
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 7
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 4
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 4
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 6
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 6
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 5
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 6
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 5
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 5
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 7
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 14
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 41
Generate MD5 hash for a string
This is sample output - yours may be different.
10

md5sum <<<"test"

unefunge · 2010-11-24 12:04:41 16

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 20

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 9
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 24
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 3
Bash: escape '-' character in filename
This is sample output - yours may be different.
4

mv -- -filename filename

unefunge · 2010-11-17 12:52:36 7

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Extract raw URLs from a file

you can also use cut instead of awk. less powerful but probably faster. ;)

Embed next line on the end of current line using sed

N: On the current line, sed will display it on pattern space, plus a \n (new line); but s/\n//: Will get rid of new line displayed on pattern space, joining the current line's end with the start of the next line Useful in scripts.

wget download with multiple simultaneous connections

check open ports without netstat or lsof

Recursive search and replace (with bash only)

Replaces a string matching a pattern in one or several files found recursively in a particular folder.

Find all clients connected to HTTP or HTTPS ports

It finds, specifically, the connections to the HTTP and HTTPS ports as source ports. You can check for destination ports as well.

list block devices

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

Print the last modified file

list block devices

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

list block devices

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

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