(This is a translation of the original article in Japanese by moratorium08.)
(UPDATE (22/3/2019): Added some corrections provided by the original author.)
Writing your own OS to run on a handmade CPU is a pretty ambitious project, but I've managed to get it working pretty well so I'm going to write some notes about how I did it.
| -- show running queries (pre 9.2) | |
| SELECT procpid, age(clock_timestamp(), query_start), usename, current_query | |
| FROM pg_stat_activity | |
| WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' | |
| ORDER BY query_start desc; | |
| -- show running queries (9.2) | |
| SELECT pid, age(clock_timestamp(), query_start), usename, query | |
| FROM pg_stat_activity | |
| WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' |
| # Install ARCH Linux with encrypted file-system and UEFI | |
| # The official installation guide (https://wiki.archlinux.org/index.php/Installation_Guide) contains a more verbose description. | |
| # Download the archiso image from https://www.archlinux.org/ | |
| # Copy to a usb-drive | |
| dd if=archlinux.img of=/dev/sdX bs=16M && sync # on linux | |
| # Boot from the usb. If the usb fails to boot, make sure that secure boot is disabled in the BIOS configuration. | |
| # Set swedish keymap |
| from flask import Blueprint | |
| from flask import url_for | |
| from flask.ext.login import current_user | |
| from flask.ext.login import login_user | |
| from flask.ext.login import logout_user | |
| from flask.ext.login import login_required | |
| from forms import LoginForm | |
| from forms import ForgotPasswordForm | |
| from forms import ResetPasswordForm |
_________ _____ _______________ _____
\_ ___ \\ \\___________ \____ / ____\ ~/.bash/cliref.md
/ \ \/| | | || _/ __ \ __\ copy/paste from whatisdb
\ \___|__ |_|_ || | \ __/|_ | http://pastebin.com/yGmGiDQX
\________ /_____ \_||____|_ /____ /_| [email protected]
20160515 \/ 1527 \/ \/ \/
alias CLIRef.txt='curl -s "http://pastebin.com/raw/yGmGiDQX" | less -i'
| Why do compilers even bother with exploiting undefinedness signed overflow? And what are those | |
| mysterious cases where it helps? | |
| A lot of people (myself included) are against transforms that aggressively exploit undefined behavior, but | |
| I think it's useful to know what compiler writers are accomplishing by this. | |
| TL;DR: C doesn't work very well if int!=register width, but (for backwards compat) int is 32-bit on all | |
| major 64-bit targets, and this causes quite hairy problems for code generation and optimization in some | |
| fairly common cases. The signed overflow UB exploitation is an attempt to work around this. |
Beautiful is better than ugly. Explicit is better than implicit.
I frequently deal with collections of things in the programs I write. Collections of droids, jedis, planets, lightsabers, starfighters, etc. When programming in Python, these collections of things are usually represented as lists, sets and dictionaries. Oftentimes, what I want to do with collections is to transform them in various ways. Comprehensions is a powerful syntax for doing just that. I use them extensively, and it's one of the things that keep me coming back to Python. Let me show you a few examples of the incredible usefulness of comprehensions.
All of the tasks presented in the examples can be accomplished with the extensive standard library available in Python. These solutions would arguably be more terse and efficient in some cases. I don't have anything against the standard library. To me there is a certain
GitHub supports several lightweight markup languages for documentation; the most popular ones (generally, not just at GitHub) are Markdown and reStructuredText. Markdown is sometimes considered easier to use, and is often preferred when the purpose is simply to generate HTML. On the other hand, reStructuredText is more extensible and powerful, with native support (not just embedded HTML) for tables, as well as things like automatic generation of tables of contents.
| # read more at https://terrty.net/2014/ssl-tls-in-nginx/ | |
| # latest version on https://gist.github.com/paskal/628882bee1948ef126dd/126e4d1daeb5244aacbbd847c5247c2e293f6adf | |
| # security test score: https://www.ssllabs.com/ssltest/analyze.html?d=terrty.net | |
| # your nginx version might not have all directives included, test this configuration before using in production against your nginx: | |
| # $ nginx -c /etc/nginx/nginx.conf -t | |
| server { | |
| # public key, contains your public key and class 1 certificate, to create: | |
| # (example for startssl) | |
| # $ (cat example.com.pem & wget -O - https://www.startssl.com/certs/class1/sha2/pem/sub.class1.server.sha2.ca.pem) | tee -a /etc/nginx/ssl/domain.pem > /dev/null |