Programming

Atom as a full IDE

• Can I turn Atom into a full C++ IDE (forum thread)
• gpp-compiler
• Creating a toolbar in Atom
  • Flex Tool Bar
    • Icons

bash

Dialogs

• Text Entry Dialog using zenity
• Maybe YAD would be better...
  • Examples
  • Ooohhh... it IS better!
    • Buttons example

Some Links

• Bash printf syntax basics

C

• Learn the Embedded C Programming Language: Understanding the Union Data Object
• printf()

C++

(Apparently, a language designed to make C programmers lose their minds...)

Converting numbers to strings

• itoa - C++ Reference

Problem Solving

• Error] cannot pass objects of non-trivially-copyable type 'std::string {aka class std::basic_string<char>}' through '…'
  • Discussion & Solution

Processing

• Make an Indoor Shooting Range w/Processing! Easy Software App
  • The App

JavaScript

• Getting current date and time in JavaScript
• Date

Arduino (Language)

• Arduino Language Reference

Data Type Conversions

char* to String

char *message = "Hello";
String myString = String(message);

String to char*

Messing about with strings & not Strings

http://www.cplusplus.com/reference/cstring/

Specifically: strcat

Memory Saving

PROGMEM

Some Libraries to Check Out

• Bounce2
• JC Button

STUPID Library Compile Warnings!!!

Dear library writers,

Please fully debug your code before release.

It's not THAT difficult. Really.

I fully understand that compiler warnings do not indicate that your code will not work as expected, BUT, compiler warnings during a build are rather disconcerting.

Arduino Libraries

PubSubClient (2.8.0)

.pio/libdeps/SugarBush_SS_Climate_BME280/PubSubClient/src/PubSubClient.cpp: In member function 'boolean PubSubClient::publish_P(const char*, const uint8_t*, unsigned int, boolean)':

.pio/libdeps/SugarBush_SS_Climate_BME280/PubSubClient/src/PubSubClient.cpp:523:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

     return (rc == expectedLength);
                   ^

FIX: Add unsigned to the definition of expectedLength on line 487 of PubSubClient.cpp

SimpleTimer (0.0.0-alpha+sha.b30890b8f7)

.pio/libdeps/SugarBush_SS_Climate_BME280/SimpleTimer/SimpleTimer.cpp: In member function 'void SimpleTimer::run()':
 
.pio/libdeps/SugarBush_SS_Climate_BME280/SimpleTimer/SimpleTimer.cpp:66:60: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

if (current_millis - prev_millis[i] >= delays[i]) {
                                               ^

FIX: Add unsigned to the definition of delays[] on line 106 of SimpleTimer.h

Troubleshooting

When trying to compile things on a Linux machine...

You get silly-ass errors like fatal error: stdio.h: No such file or directory or other files missing that just don't make ANY sense...

• sudo apt update
• sudo apt install --reinstall build-essential

'Coz sumpin' borked yer compiler install...

Some Theory Discussion

About compiling & linking

(A long winded response to a comment in a Discord channel...)

"@Tinker's description isn't entirely accurate. "

"The linker includes sections from a library that are referenced by other sections that are required. "

--

The linker is told at build time what libraries to use.

In general, the object code of a library is treated exactly like the object code of your program itself.  (This is why many Arduino libraries are so bad for bloating your final binary...)

=====

"Old compilers emitted one lump for each compilation unit (producing a .o file) and the linker would include all or none of a .o from inside a library."

--

New compilers also create one block of object code (.o file) per compilation unit.

=====

"Modern compilers break each compilation unit into many sections inside each .o file (like one per function, etc), and the linker is free to include only stuff that is referenced."

--

You may be thinking of dynamic linking.  In dynamic linking, the library is actually placed in a separate file by the linker & simply referenced from the main binary.  This is fine for programs running on a computer with storage & an OS.  (Doesn't work well on a microcontroller...)

=====

Typically "the programmer" wouldn't tell the linker what to include.

--

In a fully functional build environment (old-school "makefile" bases building or more modern IDEs...) the programmer always tells the linker what to include.  Many modern IDEs default a lot of this for you, but the process is still there.

=====

"The compiler that invokes the linker would include startup code (e.g. crt0.o) and that requires _main, which the requires more things that will be satisfied by other .o files or archive library files."

--

The compiler doesn't invoke the linker.  The linker is invoked AFTER the compiler (or multiple compilers) & acts on the object files created as output from the compiler.

=====

"Traditional *nix linkers make one pass through the list of libraries, not going back to an earlier library to get new things that may be required by a later one, so in some incestuous situations you had to include the same library more than once."

--

If you include the actual library more than once, your program will not work.  You may be thinking if the headers for the library (i.e.: `#include <library.h>`).  This is not including the library, it is including the definitions that the library uses.