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echo "aplay ring.wav" | at now + 25 min
2013-03-22 04:27:57
User: liancheng
Functions: at echo
0

The Pomodoro Technique is a time management method developed by Francesco Cirillo in the late 1980s. The technique uses a timer to break down periods of work into 25-minute intervals called 'Pomodori' (from the Italian word for 'tomatoes') separated by short breaks.

You need to prepare a short .wav file (the "ring.wav" in the sample command line). This command will trigger aplay to play ring.wav 25 minutes from now on, which can be used as a poor man's pomodoro timer.

for f ([0-9].txt) zmv $f '${(l:1::0:)}'$f
2013-03-22 01:53:42
User: khayyam
Tags: zsh
0

zsh: add leading zero ... altogether pointless, as there can only be a maximum of 10 'single digit' files, and so a maximum of 10 files the command can act on. Padding further zeros will produce '0010', '001' and so break sequance. The only proper method is to itterate the numbers like so:

i=1; for f (*) zmv $f '${(l:3::0:)$((++i))}'.txt

but this has the unfortunate side effect of incrementing the values by 1 ... which may not be desirable.

(($1 > 0)) && echo "var is a number"
2013-03-22 01:15:00
User: khayyam
Functions: echo
0

calculate if "$1" is a number ... decimals included :)

chmod u+x **/*.sh
ls -Sh **/*(.Lm+100) | tail -5
2013-03-21 20:22:11
User: khayyam
Functions: ls tail
Tags: tail ls zsh
1

zsh: list of files sorted by size, greater than 100mb, head the top 5. '**/*' is recursive, and the glob qualifiers provide '.' = regular file, 'L' size, which is followed by 'm' = 'megabyte', and finally '+100' = a value of 100

sudo port selfupdate ; echo '---------' ; sudo port upgrade outdated
zmv '(*).txt' '$1.csv'
2013-03-21 02:28:30
User: khayyam
Tags: zsh
0

Requires zsh. You might also do the following:

for (*.txt) mv $i ${i/.txt/.csv}

or I imagine the following will work in bash:

for i in "*.txt" ; do mv $i ${i/.txt/.csv} ; done

i=1; for f (*.jpg) zmv $f '${(l:3::0:)$((++i))}'$f
2013-03-21 01:51:28
User: khayyam
Tags: zsh
0

zsh example using a 'for' loop and arithmetic expression:

files matching the pattern '*.jpg' are renamed with a 3 digit prefix, keeping the previous filename and suffix.

lsof -ni TCP
2013-03-20 22:51:16
User: tsener
Tags: lsof
1

also could specify port number:

lsof -ni TCP:80

ack --type=php <string>
2013-03-20 20:27:31
User: khayyam
Tags: ack
0

The 'sample output' shows the file(s) found and the line at which '' was found (for the example I used the 'string'.)

find -type f | xargs ls -1tr
nc -l <port-number>
2013-03-20 15:25:57
User: cybertoast
-1

Simple way to test if a port is available to the public. Run this command on the "server" and run a `telnet host-ip port-number` on the client. Test by sending strings to the server, which will be displayed in the server terminal.

rpm -qa --queryformat '%{size} %{name}-%{version}-%{release}\n' | sort -k 1,1 -rn | nl | head -16
2013-03-19 21:10:54
User: mpb
Functions: head nl rpm sort
0

Interesting to see which packages are larger than the kernel package.

Useful to understand which RPMs might be candidates to remove if drive space is restricted.

count=0;while IFS= read -r -d '' line; do echo "${line#* }"; ((++count==5)) && break; done < <(find . -type f -printf '%s %p\0' | sort -znr)
2013-03-19 17:19:26
User: sharfah
Functions: echo find read sort
Tags: sort find head,
-4

This command is more robust because it handles spaces, newlines and control characters in filenames. It uses printf, not ls, to determine file size.

alias clearscrollback='clear;printf %b "\033[3J"'
for FILE in *.conf; do cp $FILE{,.`date +%Y%m%dt%M:%H:%S`}; done
hello, too
alias cls='clear;ls'
2013-03-19 12:18:47
User: opexxx
Functions: alias
Tags: ls clear
0

Clear the screen and list file

find . -type f -exec ls -s {} \; | sort -n -r | head -5
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'
2013-03-19 11:45:47
User: opexxx
Functions: alias
0

Add an "alert" alias for long running commands

lsof -i -P +c 0 +M | grep -i "$1"
netstat -an | grep --color -i -E 'listen|listening'
tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'
2013-03-18 18:55:20
User: ene2002
Functions: grep strings tcpdump
1

This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients:

tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'

nmap --script=http-waf-fingerprint --script-args http-waf-fingerprint.intensive=1 192.168.56.254
sed "s,\x1B\[[0-9;]*[a-zA-Z],,g"
2013-03-18 14:49:30
User: Zhoul
Functions: sed
0

Remove ( color / special / escape / ANSI ) codes, from text, with sed

Credit to the original folks who I've copied this command from.

The diff here is:

Theirs: [m|K]

Theirs is supposed to remove \E[NUMBERS;NUMBERS[m OR K]

This statement is incorrect in 2 ways.

1. The letters m and K are two of more than 20+ possible letters that can end these sequences.

2. Inside []'s , OR is already assumed, so they are also looking for sequences ending with | which is not correct.

This : [a-zA-Z]

This resolves the "OR" issue noted above, and takes care of all sequences, as they all end with a lower or upper cased letter.

This ensures 100% of any escape code 'mess' is removed.