netstat: Sum open connections by IP (and sort it)
The following sums up all connections (ESTABLISHED, TIME_WAIT, FIN_WAIT, etc.) and sorts it:
netstat -n | awk ' $5 ~ /^[0-9]/ {print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
Works on FreeBSD and Linux.
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Detect mobile or touch devices on both server and client
Although it's tempting flirt with detecting mobile/touch devices with CSS media queries or Javascript feature detection alone, this approach will be painful when heavily customizing a feature beyond just tweaking the looks. Eventually you will wan...
Bash: How to count and sort requests by IP from the access logs
Example
87.140.79.42 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
87.140.79.42 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
87.140.79.41 - - [23/Jan/2024:09...
PostgreSQL and its way of sorting strings
PostgreSQL uses the C library's locale facilities for sorting strings:
- First, all the letters are compared, ignoring spaces and punctuation.
- It sorts upper and lower case letters together. So the order will be something like
a A b B c C - ...
Invoices: How to properly round and calculate totals
While it might seem trivial to implement an invoice that sums up items and shows net, gross and vat totals, it actually involves a lot of rules and caveats. It is very easy to create invoices where numbers don't add up and a few cents are missing....
Steve Wozniak, Steve Jobs, and the long road to the iPad. - By Tim Wu - Slate Magazine
Now in 2010, the iPad takes the same ideas to their logical extreme. It is a beautiful and nearly perfect machine. It is also Jobs' final triumph, the final step in Apple's evolution away from Wozniak and toward a closed model.
Communities Dominate Brands: Full Analysis of iPhone Economics - it is bad news. And then it gets worse
Don't do iPhone apps.
Open the on-screen keyboard on an iPhone or iPad with Javascript
There is no way to do it. This behavior is by design. You lose.
Summarizing heredoc in Ruby and Rails
This card tries to summarize by example the different uses of heredoc.
- In Ruby
<<vs.<<-vs.<<~ - In Rails
strip_heredocvs.squish
strip_heredoc should be used for a text, where you want to preserve newlines. (multi-line -> ...
Ruby: Natural sort strings with Umlauts and other funny characters
Why string sorting sucks in vanilla Ruby
Ruby's sort method doesn't work as expected with special characters (like German umlauts):
["Schwertner", "Schöler"].sort
# => ["Schwertner", "Schöler"] ...
Migrate searchkick from Elasticsearch client to Opensearch client without Downtime
General
A general overview about why and how we migrate can be found under Migrating from Elasticsearch to Opensearch
This card deals with specifics concerning the use of searchkick.