Need help: for loop about pure-bash-bible

[dylanaraps]

It's a C style for loop with blank values. It doesn't set a loop variable, it doesn't have a condition and it doesn't have an iterator. The side-effect of this is an infinite loop.

C Style loop:

for ((i=0;i<100;i++)); do
    echo "$i"
done

Semi blank (Infinite loop with iterator and variable):

for ((i=0;;++i)); do
    echo "$i"
done

Blank

for((;;)); do
    echo "$i"
done

[deltaxflux]

Well, yes I know but I don't you got my question. I was wondering how the interpreter / compiler translate this. So I made a quick snipped in c.

#include <stdio.h>

int main() {
    for(;;)
        printf("Hello GH");

    return 0;
}

Which is compiled to:

       .file   "main.c"
        .text
        .globl  main
        .type   main, @function
main:
.LFB0:
        .cfi_startproc
        pushq   %rbp
        .cfi_def_cfa_offset 16
        .cfi_offset 6, -16
        movq    %rsp, %rbp
        .cfi_def_cfa_register 6
.L2:
        movl    $84, %edi
        call    putchar@PLT
        jmp     .L2
        .cfi_endproc
.LFE0:
        .size   main, .-main
        .ident  "GCC: (GNU) 8.1.1 20180531"
        .section        .note.GNU-stack,"",@progbits

And here is the loop if we take a closer look at L2. I mean it is hard to express but is it like:

// pseudo code
// for(
handleFor() {
  if (loop_variable, == EMPTY && condition == EMPTY && iterator == EMPTY) {
    infinite_loop= true;
  }
}