what are these numbers in c language ?

#include <stdio.h>

int main(){
    FILE *file = fopen("test.txt", "ab");
    
    fwrite("hello world", 1,4, file);
}

#include <stdio.h>

int main(){
    FILE *file = fopen("test.txt", "ab");
    
    fwrite("hello world", 1,4, file);
}

#include <stdio.h>

int main(){
    FILE *file = fopen("test.txt", "ab");
    
    fwrite("hello world", 1,4, file);
}

#include <stdio.h>

int main(){
    FILE *file = fopen("test.txt", "ab");
    
    fwrite("hello world", 1,4, file);
}

what is

and

4

4 ??

if i am not mistaken

4

4 is the number of bytes to read and

is the size of the byte which means i can increase the size of

to wherever i want to present unicodes am i wrong ?

split•9/3/23, 2:09 PM

Any question you have about the c/c++ API, use man pages:
https://man7.org/linux/man-pages/man3/fwrite.3p.html

split•9/3/23, 2:10 PM

1 is the size of the element in bytes, 4 is how many elements you want to write

split•9/3/23, 2:11 PM

Yes if you were to write Unicode, you would increase the element size

.maverkOP•9/3/23, 2:17 PM

one represents the ascii size ?