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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.
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.
example of using zsh extended globbing
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
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
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.
The 'sample output' shows the file(s) found and the line at which '' was found (for the example I used the 'string'.)
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.
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.
This command is more robust because it handles spaces, newlines and control characters in filenames. It uses printf, not ls, to determine file size.
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'
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.