I mean you didn’t give it value

I don’t how to use bool in two ways that’s why I use only false

Bruh

Looks like bubble sort. The swap value inside of if statement should have been swap = true;.

Please please please read a C book.

You are asking us to do every assignment you have and are spamming screenshots

Just wait, I think he will be banned soon due to code photos spam

We need some pastebin... https://bsd.to/

Oh, message deleted so quickly🤔

Oh, message deleted so quickly🤔

yeah I forgot to share pastebin

how can I put .o files into /obj dir which is subfolder of /project I mean /project/bin&inc&src&obj http://bsd.to/EmoM

how can I put .o files into /obj dir which is subfolder of /project I mean /project/bin&inc&src&obj http://bsd.to/EmoM

Look at this make file https://www.github.com/V01D-NULL/BreezeOS/tree/master/Breeze%20OS%2FMakefile

Look at this make file https://www.github.com/V01D-NULL/BreezeOS/tree/master/Breeze%20OS%2FMakefile

you developing an OS ?

Look at this make file https://www.github.com/V01D-NULL/BreezeOS/tree/master/Breeze%20OS%2FMakefile

32bit 🧐

Use qloader and switch to 64bit

Iam beginner how I can learn c

Iam beginner how I can learn c

No way

No way

Why

32bit 🧐

Read the readme

Use qloader and switch to 64bit

https://www.github.com/V01D-NULL/BreezeOS/tree/master/README.md

you developing an OS ?

Yeah

Taking input "1,2,3" and printing out 1 2 3 How do I do that?

int num[3]; cin >> num[0]; cin >> num[1]; cin >> num[2]; for(int i = 0; i < 3; i++){ cout << num[i] <<endl; }

Taking input "1,2,3" and printing out 1 2 3 How do I do that?

#include <stdio.h> #include <string.h> int main() { char in[] = "1,2,3"; size_t len = strlen(in); for (size_t i = 0; i < len; i++) { printf("%c", in[i] == ',' ? '\n' : in[i]); } }

Why references require complete types, not just declaration like pointers, especially in the function signature?

Since reference are internally implemented as a non-nullable pointer

Why references require complete types, not just declaration like pointers, especially in the function signature?

They dont

Hmm

Okay Thanks

random header.h: struct foo; void bar(foo& f);

Compiles just fine

#include <stdio.h> #include <string.h> int main() { char in[] = "1,2,3"; size_t len = strlen(in); for (size_t i = 0; i < len; i++) { printf("%c", in[i] == ',' ? '\n' : in[i]); } }

Thanks!

Kk Sorry

int num[3]; cin >> num[0]; cin >> num[1]; cin >> num[2]; for(int i = 0; i < 3; i++){ cout << num[i] <<endl; }

Won't it break because of the comma signs?

Took me 3 Hours to solve just 3 and then this guy 🚬😐

https://youtu.be/oY0PBQt36YM

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

https://youtu.be/oY0PBQt36YM

OUCH using "\n" instead of endl in C++ 🙈

OUCH using "\n" instead of endl in C++ 🙈

Using \n is faster because it does not flush stdout

So it's a good reason to use it over std::endl in some cases

Using \n is faster because it does not flush stdout

And why use "\n" not '\n'?

wouldn't a single character instead of an entire string save space?

I've not seen the video but generally yes. But at least a small string like "\n" will be allocated on the stack.

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

the problem seems to be at the word "int" 🤔

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

What compiler do you use?

What compiler do you use?

gcc

What compiler do you use?

the problem seems to be "rn"

but I can't figure out what'd be the right way

If I want on c to make the customer to press a 5 digit number and print the equal only, I should modolo by 10 and then devide by 2 on "if" statement?

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

This is x86_64 btw

ssize_t my_write(int edi, const void *rsi, size_t rdx) { ssize_t ret; __asm__ volatile( "syscall" : "=a"(ret) : "D"(edi), "S"(rsi), "d"(rdx), "a"(1) : "memory" ); return ret; }

does not work

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

^

Any idea how Japanese characters are printed in the BIOS (16 bit real mode assembly)?

Any idea how Japanese characters are printed in the BIOS (16 bit real mode assembly)?

Custom font

does not work

That's completely different code.

That's completely different code.

solved, I wrote something much better

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

There are no constraints for r8 to r15. Your arguments need r8.

solved, I wrote something much better

How is it?

How is it?

int munmap(void *addr, size_t length) { // 11 return __syscall(11, addr, length); }

int munmap(void *addr, size_t length) { // 11 return __syscall(11, addr, length); }

I see, It only takes 2 arguments. Sure you don't need r8 for this.

I see, It only takes 2 arguments. Sure you don't need r8 for this.

void *mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { // 9 return (void*)__syscall(9, addr, length, prot, flags, fd, offset); }

./payload/syscalls.h:10:5: error: matching constraint references invalid operand number 10 | int ret; __asm__ volatile("syscall" : "=a"(ret) : "a"(56), "D"(flags), "S"(stack), "d"(parent_tid), "10"(child_tid), "8"(tls) : "memory"); return ret; Hi, any idea what went wrong here?

Just note: rcx constraint is not "10", it is "c".

void *mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset) { // 9 return (void*)__syscall(9, addr, length, prot, flags, fd, offset); }

How is the macro?

How is the macro?

It's a real function

It's a real function

long (__syscall)(long, ...);

It's a real function

Oh it is a syscall from standard library?

Oh it is a syscall from standard library?

no

I meant header.

long (__syscall)(long, ...);

Just this?

How do you put the clobbers?

long (__syscall)(long, ...);

I wonder how is the definition of this function?

Ref: https://git.musl-libc.org/cgit/musl/tree/arch/x86_64/syscall_arch.h

^ That's the complete syscall arguments. I don't really know the way it can be implemented dynamically with single function like that.

I just realized that 4-th argument for syscall is not rcx.

I wonder how is the definition of this function?

.global __syscall .type __syscall,@function __syscall: movq %rdi,%rax movq %rsi,%rdi movq %rdx,%rsi movq %rcx,%rdx movq %r8,%r10 movq %r9,%r8 movq 8(%rsp),%r9 syscall ret

Just this?

yes

.global __syscall .type __syscall,@function __syscall: movq %rdi,%rax movq %rsi,%rdi movq %rdx,%rsi movq %rcx,%rdx movq %r8,%r10 movq %r9,%r8 movq 8(%rsp),%r9 syscall ret

May I know why do you consider it much better? I think it is more expensive as it always touches stack and clobbers registers that are not needed in most of the syscall cases. Is there a purpose behind this?

Try this one: char *newstack = (char *)mmap(NULL, 8392704, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0);

But when I use the newly allocated stack, I get: Jump to the invalid address stated on the next line at 0x0: ??? Address 0x0 is not stack'd, malloc'd or (recently) free'd Process terminating with default action of signal 11 (SIGSEGV) Bad permissions for mapped region at address 0x0 at 0x0: ???