Old thread: What are you working on, Jow Forums?
/dpt/ - Daily Programming Thread
Jackson Hughes
John Fisher
Rewriting HolyC in Common Lisp.
Michael Turner
senko would use javascript, because she's shit
Andrew Nelson
2nd for lisp is unintuitive
Ian Wood
I have a program which runs through instructions listed in an array kind of like a simulated computer which prompts the user to input 3 characters when it starts off. It uses read(STDIN, pointerToArray, length 3)
However, it sort of just skips the read() part and moves on to the next instruction cycle. Maybe it does invoke read() but the program keeps executing past that which is not an intended consequence. How can I make the program halt until I press enter on the read() function?
main()
main()
{
struct obj a;
load_program(&m);
while(1)
{
fetch(&a);
execute(&a);
sleep(1);
}
}
execute, only function that matters
void execute(struct obj *a)
{
char c[3];
if(a certain variable = 1)
//prompt the user to type in 3 letters. THIS IS THE PART THAT GETS SKIPPED
read(0, c, 3);
a->id=c;
else
//continue with the other statements
}
other functions if it matters to you
void load_program(struct obj *a)
{
//basically just initializes all variables of a
}
void fetch(struct obj *a)
{
//basically just points to a current part of the program
}
Joseph Long
Senko is as cute as C++, as useful as Haskell, and as competent as Go.
Joshua Foster
How did /dpt/ learn git?
Zachary Anderson
Isaiah Hughes
Your terminal is buffering input, so your program won't even see it until you press enter.
You can set your terminal into something called "raw" mode which stops it from doing that, but that's not usually something you want to fuck around with.
Christopher Morgan
>as competent as Go
what did she mean by this
Noah Adams
but why won't the program halt when doing read()? If I recall, read is a syscall which halts the process until it has finished
Dominic Ward
Cute!
Jayden Morgan
>If I recall, read is a syscall which halts the process until it has finished
That not always true, but is the "default" behaviour for it most of the time.
Anyway, rereading your question, it sounds like you've forgotten to account for the fact that newline is a character in the buffer, so there are actually 4 characters you want to read.
Kevin King
By using magit from within emacs.
Brayden Hernandez
Bump for the best loli
Bentley Myers
Ian Sanders
Is there something like magit on vscode?
Leo Perez
Just learn emacs. I don't know of anything coming close to magit without emacs.
Jaxson Ross
Are there any good programming channels on Youtube besides Computerphile ? Most of the stuff I come across is either greasy self help selling six figure dreams or some web dev crap I couldn't care less about.
Thomas Fisher
WHAT THE FUCK IS YOUR PROBLEM YOU DISGUSTING PEDO SCUM
WHY CAN'T YOU BE DISGUSTING SOMEWHERE ELSE
I FUCKING HATE YOU SO MUCH
Andrew Cook
conference video channels are usually good, e.g. cppcon, icfp
this
Robert Howard
Ok, reddit-kun. Here you go.
Nathan Watson
my $ref={(professor=>[qw(lamp shade camphor oil bing)],
student=>[qw(lamp shirt tea)],
stacy=>[qw(phone laptop dildo chad silver)],
)};
my @res=grep
{
grep $_=~/lamp/,@{$ref->{$_}};
}keys %{$ref};
say "@res";
Does it look very ugly to you?
Zachary Powell
rararu
David White
It's not Lisp or Forth, so it's ugly by default.
Juan Martinez
so how would I make it interrupt until 4(minus 1) characters are typed in?
Dylan Butler
Change the 3 to a 4.
But really, do you need to use the low-level IO functions here? I'd typically recommend you use getline() for interactive or otherwise line-based programs.
Ethan Hall
>But really, do you need to use the low-level IO functions here?
yes. The tutor required us to use syscall(2) so I lied that I used read() :))))))
Just to make it simpler to understand. I mean syscall(0, 0, c, 4) is basically the same but it's more flexible
Jaxson Bell
why the fuck are so many programmers autistic anime pedophiles
please fuck off
Austin Gomez
You can get away with not hard-coding all of these random numbers by calling it like
syscall(SYS_read, STDIN_FILENO, ...)
But anyway, increase your buffer size so it's 4 instead of 3, and discard the newline.
Samuel Robinson
no u!
we were programming first
Carter Brooks
There's for "people" like you. Just stick to that instead of shitting up a pedophile website.
Hudson Nelson
You keep coming back for more, don't you?
Nicholas Perez
Competent at making even retards productive.
Jordan Taylor
why do you come to an imageboard for autistic anime programmers? you secretly like it
Austin Davis
man git
Samuel Clark
No, nobody likes you and you willd die alone.
Ian Price
Why aren't you? Please kindly do the fucking off.
Jaxon Watson
Easton Powell
Luke Cook
>unironically uses the term 'cyberlibertarian' when discussing ecchi
0/10 into the trash
Jordan Richardson
Andrew Gonzalez
woman git
shitlord
Dominic Peterson
...
Daniel Clark
This:
Michael Brown
this
so tired of these misogynists
Brody Scott
Hoe about demuxing it with ffmpeg? Its C libraries (libavformat, libavcodec etc) are quite easy to use.
Sebastian Sanders
Not him but I'm pretty sure he's being ironic.
Jace Scott
I'm pretty sure I still want him gone.
Luis Green
Well I can't fault you there.
Joseph Reed
Give me ideas for a project that is not necessarily web related at it's core, but for which a web based interface would make sense for demonstration purposes.
>something you could actually use in your everyday life
>anything else you can think of that might be cool
my interests include
>engineering
>math
>physics
>EE stuff
>typical memes like neural networks, but I probably won't have the required datasets for that
I guess I just don't want to make another game that noone will play.
Aiden Gray
still just instantly skips the read syscall. I have even tried to fork it and have the parent wait for the child, which does the syscall and then exits, with mild success but it still immediately(although now with a slight delay) proceeds to the next part of the program
fooken frustrating
Brandon Moore
Parker King
what's the data you get out of it?
what's the return value?
Aaron Edwards
read just makes the user type in 3 chars to give the struct an ID, say ABC or something so it doesn't return anything. Just directly accesses the variable in memory
Benjamin Stewart
oh shit, maybe the syscall is skipped because I haven't assigned its return value to any variable. I will try that
Levi Torres
it returns how many characters it read, or -1 if an error happened
Wyatt Rivera
is it really skipped? try running your program under strace to see if it is genuinely skipped or just didn't do what you expected it to do
Ethan Myers
nope, didn't do anything
Anthony Gutierrez
>if (variable = 1)
>variable = 1
>=
shiggydiggy thats just you being lazy, not your actual code
Dylan Hill
>tfw when to shy to contribute to cool project while fairly sure i can do it (`._.)
Hunter Hill
did strace -e read ls -l
none of the read syscalls used STDIN so I guess it got skipped
Grayson Long
It's OK. You can have goals and work towards them. Who knows, some day you might wake up and see an opportunity to make a commit and feel willing to do so!
You can do it, user, all in your own time.
Hudson Robinson
Write a shared_ptr on a whiteboard and you're hired!
Matthew Nelson
why are you running ls?
Jacob Murphy
If you can't do that you should just fucking stop writing in C++ immediately and go back to Python.
Jayden Hughes
how hard is it learning assembly compared to learning a high level programming language?
Angel Murphy
nvm about that, I forgot how strace worked.
Aiden Hernandez
Most operators are very basic. Add, move, shift, etc. Then there are some opcodes that are wizard level. I'd say go for it if you are interested, just don't expect to be making rollercoaster tycoon in a week.
I like this resource for x86 opensecuritytraining.info
>What are you working on, Jow Forums?
Learning some things about Kotlin. I am getting closer to getting my raw h264 frames over tcp.
Nathan Flores
Thank you
Nolan Wright
because I have only used strace once in my life and that was a few months ago. Please excuse me for my retardedness.
Would
strace -e read ./compiledprogram.out
give me the desired results?
Josiah Walker
>tfw too retarded to get into computer vision
i... i only made it through trig...
Gavin Ortiz
look mom, I memorized it all
Logan Sullivan
I am going to put up an .io web game that is Jow Forums related, give me some ideas.
Jaxon Green
>memorized
Don't call us we'll call you.
Aiden Murphy
You need a logo and a good domain name first.
Angel Gutierrez
this, also makes it anime related
Brandon Anderson
Why should one learn Assembly?
Isaac Morales
There's no actual reason to use assembly outside of kernel development.
Caleb Davis
I've already put up a few, they are not hard, literally just switching out graphics, but instead of bullets/instant projectiles like most .io clones I'm going to make it less violent, characters will throw items that have hang time.
I thought first of a 5v5-10v10 border crossing game where 10 trumps on top of the wall throw projectiles to knock out the jumping mexicans (other team) who are trying to jump over the border, if enough mexicans jump over the border then the defending team loses that round, there will be leaderboard and win/loss stats for profiles.
Eli Johnson
Anyone worked on sqlite in C(or C++) and saved an array to a BLOB?
Would this be the correct syntax assuming you have prepared the INSERT query already?
rc = sqlite3_bind_blob(stmt, index_of_query, array, sizeof(array), NULL);
if (rc != SQLITE_OK) {
printf("ERROR: %s\n", sqlite3_errstr(rc));
sqlite3_close(db);
return;
}
and to retrieve it, would this be the correct syntax assuming you have prepared the SELECT query already?
if (sqlite3_step(stmt) == SQLITE_ROW)
{
unsigned int *temp = (unsigned int*)sqlite3_column_blob(stmt, 0);
memcpy(array, temp, sizeof(temp));
Lincoln Cooper
What about for like reverse engineering stuff? Isn't that how they make emulators or port games to linux and stuff? by knowing assembly?
Joseph Sullivan
I don't use it a lot either, but that looks good to me
Xavier Hernandez
>Anime: From Akira to Princess Mononoke
kek
Jack Cox
Thank you, user.
Juan Martinez
>What are you working on, Jow Forums?
Test coverage and docs. Pretty much done until I want to work on the standalone server.
Ian Parker
cracking, hyperoptimized stuff, reverse engineering, gaining a slightly better understanding of the underlying electronics hardware
Dylan Sanchez
Writing compilers.
Xavier Martin
Does anyone know why I keep getting the compile time error "undefined reference to `foo()'"? Both g++ ad clang++ give me the same error.
foo is a non-member function of class1.
declaration of foo on class1.h
bool foo();
definition of foo on class1.cpp
#include "class1.h"
bool foo()
{
std::cout
Levi Williams
probably because class1.cpp and class1.h wont compile
Cameron Price
Also probably forgot to add class1.cpp to compiler command
Caleb Howard
It's not a compile time error but a linker error.
How are you compiling your project?
Ayden Jones
Github documentation and Atlassian tutorials, then practice of course. Before blindly using a flag, look it up first. Flags are usually used to combine more than one simple operation. Eventually you will understand how it works, how the operations work on it, and you will finally grok it.
Dominic Williams
If O(nm+n)=O(nm), is O(nm+k)=O(nm)? Or do you have to keep that linear factor in this case?
Nolan Ross
Memorizing the standard does not mean you can write good code.
David White
what are n m and k? if m and k are constants then O(nm+k) = O(n)
Ayden Thompson
It's not a problem of memorisation, brainlet.
Sebastian Morris
>clang-8: error: linker command failed with exit code 1 (use -v to see invocation)
Apparently you're right, user.
I'm using VS Code and from the looks of it I didn't configure the tasks.json file properly. I thought this kind of stuff would work out of the box. Well, shit! I will look into it.
Ethan Walker
Why would they be constants?
Say the O(nm+n) algorithm is iterating over a n*m 2D array and then a single row of size n for whatever reason. Clearly this is just O(nm).
Say the O(nm+k) algorithm is iterating over a n*m 2D array and then a different 1D array of size k. Can I say it's O(nm) or is it O(nm+k)?
Jose Gonzalez
Post them!