Still need to research this: [WayBack] I search for way to automatically generate class body from interface definition… – Jacek Laskowski – Google+
–jeroen
Archive for January, 2019
On my research list: Delphi; automatically generate class body from interface definition
Posted by jpluimers on 2019/01/23
Posted in Conference Topics, Conferences, Delphi, Development, Event, ModelMaker Code Explorer, Software Development | 2 Comments »
Don’t forget your padding… playing with the APK format of a sample “Hello world” Android app
Posted by jpluimers on 2019/01/23
Don’t forget your padding: Hello,I’m playing with the APK format of a sample “Hello world” Android application.my (first) goal is to be able to rebuild an APK from a unzipped one… – Paul TOTH – Google+
References: RSA Algorithm
–jeroen
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Posted in Android, Development, Encryption, Mobile Development, Power User, Security, Software Development | Leave a Comment »
CDATA inside JavaScript or style section of HTML? They are for backward compatibility. Sometimes compatibility with ancient browsers.
Posted by jpluimers on 2019/01/23
As a back-end person, sometimes I wondered about CDATA in front-end HTML code was for, especially in JavaScript and CSS style elements.
[WayBack] HTML vs. XHTML – WHATWG Wiki explains how to be compatible with XHTML, HTML, XML based tools and older browsers:
The following code with escaping can ensure script and style elements will work in both XHTML and HTML, including older browsers.
In both cases, XML ignores the first comment and then uses the
CDATAsection to avoid the need for escaping special characters<and&within the rest of the contents (with subsequent JavaScript comments added within to ensure the HTML-oriented code is ignored by JavaScript).In HTML, older browsers might display the content without the content being within a comment, so comments are used to hide this from them (while modern HTML browsers will run code inside the comments). The subsequent JavaScript comment is added to negate the text added for the sake of XHTML.
The
<style>requires the/**/comments since CSS does not support the single line ones.<!----> ... //--><style type="text/css"><!--/*--><![CDATA[/*><!--*/ ... /*]]>*/--></style>If not concerned about much older browsers (from which one is hiding the HTML) one can use the simpler:
//<style>/*<![CDATA[*/ /*]]>*/</style>Also note that the sequence “
]]>” is not allowed within aCDATAsection, so it cannot be used in true XHTML-embedded JavaScript without escaping.
–jeroen
via:
- [WayBack] HTML comments in CSS? – Stack Overflow
- [WayBack] Should I use <![CDATA[…]]> in HTML5? – Stack Overflow
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Posted in CSS, Development, HTML, HTML5, JavaScript/ECMAScript, Scripting, Software Development, Web Development | Leave a Comment »
Convert Indesign Sketch to code: Petra Sketch Plugin | Melbourne | Applying Code
Posted by jpluimers on 2019/01/22
Interesting code generator from 3D models into Xamarin, Delphi or Oxygene code:
[WayBack] Petra Sketch Plugin | Melbourne | Applying Code
Convert Sketch drawings to iOS, macOS, Android and Windows native drawing code.
[WayBack] Documentation of Petra Sketch Plugin | Melbourne | Applying Code
Via:
- [WayBack] Hi! A long time ago, there was a cool app winner that was about generating Delphi code from mockups or something along those lines. Anyone remembers … – Andrea Raimondi – Google+
- [WayBack] Petra Wins Embarcadero Cool App for December – Embarcadero Community
–jeroen
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Posted in .NET, C#, Delphi, Development, Software Development, Xamarin Studio | Leave a Comment »
Dilbert Comic Strip on 1995-11-09 | Dilbert by Scott Adams
Posted by jpluimers on 2019/01/22
- The caption says, “Saint Dogbert enters the Land of Cubicles searching for the demons of stupidity.” Dogbert walks down the hall wearing a bishop’s miter and holding a scepter.
- The caption says, “Suddenly he finds an over-promoted computer guru spouting useless database concepts.” A man sits at a conference table with two glassy-eyed co-workers. The man says, “You’d be fools to ignore the boolean anti-binary least-square approach.”
- The caption says, “The monster is dispatched to the dark world by the sight of its most feared object.” Dogbert stands on the conference table holding a document in front of the man. Dogbert says, “Look! Actual code!” The man’s head melts into his shirt and a co-worker says, “Cool!”
Source: [WayBack] Dilbert Comic Strip on 1995-11-09 | Dilbert by Scott Adams
–jeroen
via: [WayBack] architecture – Why does the .NET framework have no concept of classes as first-class types? – Software Engineering Stack Exchange
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Posted in Development, Software Development | Leave a Comment »
Passwordless SSH
Posted by jpluimers on 2019/01/22
Note: if the system you SSH from is ever compromised, then assume the passwordless targets are also compromised!
- [WayBack] How to set up ssh so you aren’t asked for a password
- [WayBack] Git – Generating Your SSH Public Key
- [WayBack] SSH/OpenSSH/Keys – Community Help Wiki
- [WayBack] Understanding SSH Key Pairs :: WinSCP
- [WayBack] How To Set Up SSH Keys | DigitalOcean
–jeroen
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Posted in *nix, *nix-tools, Communications Development, Development, Internet protocol suite, Linux, openSuSE, Power User, SSH, SuSE Linux, TCP, Tumbleweed | Leave a Comment »
Why don’t I get the warning W1036 Variable “‘MyStrings’ might not have been initialized”…
Posted by jpluimers on 2019/01/21
Historically, [WayBack] W1036: Variable '%s' might not have been initialized (Delphi) has had a lot of gotchas.
The most important still is that it never show for managed types (strings, interfaces, etc).
Usually W1036 shows for non-managed types, but Dan Hacker has found a new case where it does not in [WayBack] Why don’t I get the warning W1036 Variable “‘MyStrings’ might not have been initialized’ if the StringsToDo parameter in DoSomething is defined as a var… – Dan Hacker – Google+
He noticed it in Delphi XE and 10.2 Tokyo.
I tested it with the Win32 compiler in XE8.
This warns:
program W1036;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.Classes;
procedure DoSomething(var StringsToDo: TStringList); // <-------- this line makes the difference
begin
//do nothing
end;
procedure Test;
var
MyStrings : TStringList;
begin
MyStrings.Free; {W1036 warning if StringsToDo param is NOT var}
DoSomething(MyStrings);
end;
begin
end.
This does not warn:
program W1036;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.Classes;
procedure DoSomething(StringsToDo: TStringList); // <-------- this line makes the difference
begin
//do nothing
end;
procedure Test;
var
MyStrings : TStringList;
begin
MyStrings.Free; {W1036 warning if StringsToDo param is NOT var}
DoSomething(MyStrings);
end;
begin
end.
initially, I misread his report and reacted wrongly on the cause (but rightly on the suggested use case of var and of TStringList):
Because a var parameter means that the caller should pass in an initialised parameter. Otherwise it should be an
outparameter, not avarparameter.
varparameter for reference types likeTStrings(only pass asTStringListif it deliberately is not compatible withTStrings) is a risky thing anyway, because the called method can overwrite it and then the caller has to notice the change, then decide what to do with the previous value (likely free it).
I later correct myself:
Looking better, I think it is a compiler issue.
The only difference between nothing and var is the loading of the parameter as a pointer:
with
var//W1036.dpr.16: MyStrings.Free; {W1036 warning if StringsToDo param is NOT var}
//004CD924 8B45FC mov eax,[ebp-$04]
//004CD927 E8B8A6F3FF call TObject.Free
//Project1.dpr.17: DoSomething(MyStrings);
//004CD92C 8D45FC lea eax,[ebp-$04]
//004CD92F E8E0FFFFFF call DoSomethingwithout
var//W1036.dpr.16: MyStrings.Free; {W1036 warning if StringsToDo param is NOT var}
//004CD924 8B45FC mov eax,[ebp-$04]
//004CD927 E8B8A6F3FF call TObject.Free
//Project1.dpr.17: DoSomething(MyStrings);
//004CD92C 8B45FC mov eax,[ebp-$04]
//004CD92F E8E0FFFFFF call DoSomething
So:
- with a
var, a pointer to the instance ofMyStrings(obtained by aleainstruction) gets pushed on the stack - without a
var, the instance ofMyStrings(obtained by amovinstruction) gets pushed on the stack.
For the difference metween mov and lea, and the use of [] brackets, see:
- [WayBack] assembly – What is the difference between MOV and LEA? – Stack Overflow
- [WayBack] assembly – What do the brackets mean in x86 asm? – Stack Overflow:
Given the following
code:L1 db "word", 0
mov al, [L1]
mov eax, L1What do the brackets ([L1]) represent?
–jeroen
Source: Why don’t I get the warning W1036 Variable “‘MyStrings’ might not have been i…
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Posted in Conference Topics, Conferences, Delphi, Development, Event, Software Development | 3 Comments »
Linus Torvalds – Google+: Working gadgets: Ubiquiti UniFi collection (and a whole bunch of Unifi/Ubiquiti/Ubtn links).
Posted by jpluimers on 2019/01/21
Seems my interest in Ubiquiti needs more research: [WayBack] Linus Torvalds – Google+: Working gadgets: Ubiquiti UniFi collection.
Hopefully by now I’ve time to re-design the WiFi coverage in the house and invest in a few of those access points.
Related:
- [WayBack 1/2/3] Vincent Parrett commented: I have two of these (along with a cloudkey and edgemax switch) in my house, perfect wifi coverage over the whole house. I’m also using ubnt routers and switches for our servers in the US. Less impressed with the edgerouter pro, has overheating issues due to poor thermal design, but still easy to use and configure etc.
- [WayBack 1/2] Dear interwebz, what and how many #Ubiquiti devices do I need to cover 5Ghz WiFi with seamless roaming on 3 stacked floors of 10×10 meter home office se… – Jeroen Wiert Pluimers – Google+
- [WayBack] Use a third party POE switch – Ubiquiti Networks Community
- Apart from alternatives, this observation “FWIW my experience with the TP-Link SF and SG series switches is poor. I have had more than average hardware failures with these, and some versions silently drop packets (most notably BDPUs if using STP).”
- [WayBack] Solved: UAP-AC-Lite with TP-Link TL-SG1008PE – Ubiquiti Networks Community
- Powering the UAP-AC-Lite with a Mikrotik RB960PGS (also known as hEX PoE) over PoE works fine
- [WayBack] Use a third party POE switch – Ubiquiti Networks Community
- Tweakers.net:
- PoE from other vendors:
- RB260GSP (does passive PoE only) – [WayBack] POE – UAP-AC-LR with Mikrotik RB260GSP? – Ubiquiti Networks Community
- RB960PGS also known as hEX PoE (does 802.3af, see below)
- Mikrotik needs to make up their mind, as they ship a 24V power supply which cannot power any 802.3af/802.3at devices. The 48POW power supply enables 802.3af for the RB960PGS hEX PoE: [WayBack] hEX PoE (RB960PGS) – Need 48V Power Supply – MikroTik
- Ubiquiti UniFi AP-AC LITE production week 2016-38 (first four digits of serial number 1638) and more recent support 802.3af: [WayBack] Bekijk reactie – [Ubiquiti-apparatuur] Ervaringen & Discussie – Deel 2 – Netwerken – GoT
- 48v PoE should work too, but it is better to assume date code 1646 (officially this is 1641, but not all ones function correctly):
Controller
- The easiest way to configure, is to have a Unifi Controller running in your network.
- The controller can be a [WayBack] Ubiquiti Networks – UniFi® Cloud Key, but does not have to be: a VM, Docker Container, Raspberry Pi, or other solution can work just as well.
- Unifi Controller Versions are released at irregular times, usually at least once a month; I used these places to track them:
- [WayBack] UniFi Updates Blog – Ubiquiti Networks Community (a bit awkward because the overview has message summaries in addition to the topic)
- [WayBack] UniFi Updates Blog | UniFi Forum NL (easier to track as the message overview is a simple table that has a message topic column)
- [WayBack] Chocolatey Gallery | Ubiquiti UniFI Controller 5.8.28
- When using a CloudKey, please avoid sudden power loss: it can brick the database
- There are various ways to safely power it down:
- The button on the side is a power down button (see image on the right I got the documentation at [WayBack] https://dl.ubnt.com/guides/UniFi/UniFi_Cloud_Key_UC-CK_QSG.pdf)
- On the CloudKey interfaces themselves: [WayBack] Solved: Re: Correct way to remove Cloud Key – Ubiquiti Networks Community:
- There is the “Shutdown” button, in the Unifi Controller UI (https://a.b.c.d.e:8443/manage): Settings -> Maintenance -> Cloud Key Operations -> Shutdown Cloud Key
- Similar in the cloud environment as that is a kind of wrapper around the local controller: Settings -> Maintenance -> Cloud Key Operations -> Shutdown Cloud Key
- There is a “Power Off” button in the Unifi Cloud Key UI (https://a.b.c.d.e:8443/manage/main): Maintenance -> Power Off
- There is the “Shutdown” button, in the Unifi Controller UI (https://a.b.c.d.e:8443/manage): Settings -> Maintenance -> Cloud Key Operations -> Shutdown Cloud Key
- Resurrecting can be needed, and is relatively easy if you can still SSH into it as root:
- [WayBack] Solved: Unifi Cloud Key Nonfunctional After Reboot – Ubiquiti Networks Community
- [WayBack] Solved: Re: Unifi Cloud Key Nonfunctional After Reboot – Ubiquiti Networks Community
-
service unifi stop mongod --repair --dbpath /srv/unifi/data/db service unifi start
-
- Sometimes it will not shutdown, so you have to force it, with the risk of having to restore a database backed-up on SD card: [WayBack] Solved: Re: Cloud Key won’t shutdown – Ubiquiti Networks Community
- More recent CloudKey use a USB C plug, not Micro USB plug [WayBack] Solved: PoE injector for Cloud Key – Ubiquiti Networks Community
- Powering was a bit tricky:
- Powering a CloudKey with a TP-Link TL-SG1008PE works fine
- Powering a CloudKey with a [WayBack] MikroTik Routers and Wireless – Products: hEX PoE (RB960PGS)
- over PoE fails (it does not come up at all, the Mikrotik PoE led flashes red once when inserting the network cable).
- over USB fails as well (the CloudKey gets in a reboot loop: white led flashes in the same pattern like for good PoE boot, but goes dark after ~20 seconds, then after a few seconds rinse repeat. This despite the USB 1A power delivery of the Mikrotik: [WayBack] Cloud Key USB-C power adapter recommendation – Ubiquiti Networks Community. CloudKey boot cycle starts a few seconds after the PoE light on the Mikrotik becomes red (meaning PoE is active).
- Others have better luck on USB: [WayBack] Cloud Key micro-USB power supply electrical requirements (ripple/noise/voltage min/max)? – Ubiquiti Networks Community
- I have tested the RBS960PGS with firmwares 6.39.2 and 6.42.7 after reading the [WayBack] Manual:PoE-Out – MikroTik Wiki.
- Passive 48V PoE is also a possible solution: [WayBack] UniFi – Cloud Key Troubleshooting Guide – Ubiquiti Networks Support and Help Center: Powering the UniFi Cloud Key
- There are various ways to safely power it down:
- Configuration:
- Online configuration Portal: https://unifi.ubnt.com/
- This works way better at device discovery than the Chrome plugin “Ubiquiti Device Discovery Tool” below
- You can perma-link to your local device; it looks like
https://unifi.ubnt.com/5.8.24.0/unifi/site/default/dashboard?d=############000000000#######000000000#######00000000########where#are digits,0are usually zero digits and5.8.24.0is.0prepended by the first 3 parts of your Unifi Controller Version (mine hadVersion 5.8.24-11016at that time).
- [WayBack] Ubiquiti Networks – Search | discovery tool
- [Archive.is/WayBack] Ubiquiti Device Discovery Tool – Chrome Web Store
- Note that temporarily there was a fake Crome tool: [WayBack] Fake Ubiquiti Device Discovery Tool discovered on the Chrome Web Store – Ubiquiti Networks Community
- [WayBack] Java https://dl.ubnt.com/tools/beta/discovery-tool/ubnt-discovery.zip
- [Archive.is/WayBack] Ubiquiti Device Discovery Tool – Chrome Web Store
- Online configuration Portal: https://unifi.ubnt.com/
- Wireshark
- You can capture AP traffic using Wireshark because the Access Points all support SSH
- UniFi information:
- [WayBack] UniFi Network Planner
- [WayBack] Ubiquiti Networks Support and Help Center
- [WayBack] Home – Ubiquiti Networks Community
- [WayBack] Solved: roaming wifi between 3 x UAP AC LR – Ubiquiti Networks Community
- [WayBack] Wireless LAN Roaming FAQ – Ubiquiti Networks Community
- SSIDs and radios:
- [WayBack] Solved: Re: set AP to 2.4 and 5 GHz on different ssid – Ubiquiti Networks Community
- [WayBack] Solved: Re: How setup a separate 2.4 and a separate 5 ghz ssid – Ubiquiti Networks Community
- [WayBack] Solved: Re: Splitting 2.4 / 5 Ghz onto different SSID or not – advice and guidance request please. – Ubiquiti Networks Community
- [WayBack] Solved: Re: How to force 5 Ghz – Ubiquiti Networks Community
- [WayBack] Solved: Re: Max 4 SSIDs per AP, how many per controller? – Ubiquiti Networks Community
- [WayBack] Solved: Re: “A maximum of 4 wireless networks are allowed per wlan group when connectivity monitor is e – Ubiquiti Networks Community
- [WayBack] Ubiquiti Networks – Downloads
- [WayBack] UniFi demo dashboard
- [WayBack] Wireless APs and Switches | UniFi | b3n.org
Splitting 5Ghz and 2.4Ghz SSIDs: two ways (I think the second is cleaner)
- Either have one WLAN group with a set of SSIDs, then in each access point disable the 2.4Ghz SSID on the 5GHz radio, and disable the 5Ghz SSID on the 2.4Ghz radio
- Have different WLAN groups with an SSID (or set of SSIDs) for each frequency, then in each access point select the appropriate group for each radio
For both the first and second one, you need to configure under “Config” -> “WLANs”.
For the second one, you can clone from the first, then change the SSID names.
–jeroen
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Posted in Power User, Ubiquiti, WiFi | Leave a Comment »
Installing as a LAN -> WiFi bridge: FRITZ!WLAN Repeater 1750E
Posted by jpluimers on 2019/01/21
I have a bunch of [WayBack] FRITZ!WLAN Repeater 1750E | Overview | AVM International devices; this is the quickest way to install them as LAN -> WiFi bridge (connect ethernet to your LAN; use the WiFi as a bridge).
- Connect the FRITZ!WLAN to your LAN
- Connect the FRITZ!WLAN to power
- Connect your laptop to the WiFi SSID
FRITZ!WLAN Repeater 1750Ewith password00000000(that eight times a zero) - Set your laptop with a fixed IP address
192.168.178.127with netmask255.255.255.0and gateway192.168.178.2for WiFi. - Connect to your FRITZ!WLAN at http://192.168.178.2
- Setup your FRITZ!WLAN for the first time (password, country) and have it reboot
- Logon to the FRITZ!WLAN
- Change the WiFI password and the SSID for 2.4 Ghz and 5.0 Ghz channels (I use a different SSID for both as many Fritz!Box devices have both bad 2.4Ghz performance and a hard time to automatically switch from 2.4Ghz to 5.0Ghz on the same SSID automagically).
- Change your laptop to use DHCP on WiFi
- Reconnect to the Fritz!Box with the new SSID and password
–jeroen
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Posted in Fritz!, Fritz!WLAN, Internet, Power User | Leave a Comment »
Google Sheet with forwarding addresses. Please feel free to add yours….
Posted by jpluimers on 2019/01/21
[WayBack] I have created a Google Sheet with forwarding addresses. Please feel free to add yours- only the info you are comfortable with. Please DO NOT add full e… – Di Cleverly – Google+
[Archive.is] Forwarding Addresses – Google Sheets
–jeroen
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Posted in G+: GooglePlus, LifeHacker, Power User, SocialMedia | Leave a Comment »
The Wiert Corner - irregular stream of stuff 