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 1
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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Print the 10 deepest directory paths

bash function to check for something every 5 seconds

checkfor: have the shell check anything you're waiting for. 'while : ; do' is an infinite loop '$*' executes the command passed in 'sleep 5' - change for your tastes, sleep for 5 seconds bash, ksh, likely sh, maybe zsh Ctrl-c to break the loop

Formatted list - WWNs of all LUNs

Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array) (shown: RHEL5 usage) Debian usage: $ # for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done

Display Spinner while waiting for some process to finish

alternatively, run the spinner for 5 seconds: timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

IBM AIX: Extract a .tar.gz archive in one shot

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.

Make alias pemanent fast

Simple function to permanently add an alias to your profile. Tested on bash and Ksh, bash version above. Here is the ksh version: PERMA () { print "$@" >> ~/.profile; } Sample usage: PERMA alias la='ls -a'

Find longest running non-root processes on a machine

If you have ever been trying to look for a list of processes based on their elapsed time you don't need to look any further. This command lets you find the list of processes ordered in a reversed order (oldest at the top) that have been running for over an hour on your system. Any system processes are filtered out, leaving only user initiated ones in. I find it extremely useful for debugging and performance analysis.

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"

Spell check the text in clipboard (paste the corrected clipboard if you like)

xclip -o > /tmp/spell.tmp # Copy clipboard contents to a temp file aspell check /tmp/spell.tmp # Run aspell on that file cat /tmp/spell.tmp | xclip # Copy the results back to the clipboard, so that you can paste the corrected text I'm not sure xclip is installed in most distributions. If not, you can install x11-apps package

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