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Re: What Thinkest Thou Of LO Donate Banner?

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vallor <vallor@vallor.earth> news:10h2u70$36bnl$1@dont-email.me Sun, 07 Dec 
2025 04:01:36 GMT in comp.os.linux.advocacy, wrote:

> At Wed, 3 Dec 2025 22:03:12 -0000 (UTC), Gremlin <nobody@haph.org>
> wrote:
>> read_file: rem as the name implies, it reads bytes into a buffer. :-)
>> rem as with write_file, you need to predefine the dx register for the
>> rem buffer where you want the info stored. Like so:
>> dx=varptr(buffer(0)) rem if you don't, this routine will not work, or
>> will overwrite some rem other section of memory. And for virus
>> coding, this is very bad! :) rem cx register is how many bytes to
>> read :) if file_handle>4 then ax=&hex3f00 bx=file_handle cx=bytesize
>> int86(&hex21,ax,bx,cx,dx,na,na,na,na,na) bytesread=ax endif return
> 
> Hey, just wanted to mention that Linux used to use int86(0x80,...)
> for its own syscalls.  In C, read(2) is the way to read into a buffer,
> which would set up the syscall (call to interrupt 0x80).  I guess in DOS,
> C would set up the interrupt call similar to how you show, and then
> call the interrupt.

I remember from writing elf binaries. <G> Fun and educational times.

> Modern processors have an actual SYSCALL intrinsic, so no more interrupt
> call to enter the kernel.

Windows API calls can still be used to enter the kernel. Modern CPUs 
running a flavor of DOS still respect DOS interrupt calls when running in 
'real mode'  kernel entrance. It's known as 'real mode' vs 'Protected mode 
and virtualization'

As for Linux, here's a c/p from google AI:

Yes, Linux absolutely uses interrupts and interrupt calls
(like the syscall instruction on modern CPUs) to allow user-space 
processes to request kernel services, enabling privileged kernel access 
for tasks like file I/O or process management, with specific mechanisms 
like IRQs for hardware, `syscall` for system calls, and exceptions for 
errors all transitioning the CPU to kernel mode (Ring 0) to execute 
privileged code. Modern systems use efficient instructions like syscall 
for system calls, but the core principle of interrupt-driven transitions 
to kernel space for privileged operations remains fundamental. 
***

The 286 was the first to offer protected mode access. It was significantly 
improved with the 386. Modern CPUs still offer real mode as well. So, I'm 
not sure what you mean exactly by a modern CPU in this instance? Or what 
you mean by no more interrupt call to enter the kernel? 


> I remember DOS interrupts 0x21 (DOS itself), and 0x10(BIOS, iirc).

<G> It takes me back man. 



-- 
Liar, lawyer; mirror show me, what's the difference?
Kangaroo done hung the guilty with the innocent
Liar, lawyer; mirror for ya', what's the difference?
Kangaroo be stoned. He's guilty as the government

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Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-02 20:13 +0000
  Re: What Thinkest Thou Of LO Donate Banner? John Ames <commodorejohn@gmail.com> - 2025-12-03 08:39 -0800
    Re: What Thinkest Thou Of LO Donate Banner? "Carlos E.R." <robin_listas@es.invalid> - 2025-12-03 19:42 +0100
    Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-03 22:03 +0000
      Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-03 22:36 +0000
        Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-04 03:05 +0000
          Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-04 14:24 +0000
            Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-04 14:35 +0000
              Re: What Thinkest Thou Of LO Donate Banner? John Ames <commodorejohn@gmail.com> - 2025-12-04 08:21 -0800
                Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-04 18:05 +0000
                Re: What Thinkest Thou Of LO Donate Banner? John Ames <commodorejohn@gmail.com> - 2025-12-04 10:09 -0800
                Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-04 19:09 +0000
                Re: What Thinkest Thou Of LO Donate Banner? John Ames <commodorejohn@gmail.com> - 2025-12-04 11:11 -0800
                Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-04 19:55 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-04 22:47 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-05 00:15 +0000
              Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-04 22:48 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-05 00:14 +0000
            Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-04 22:47 +0000
              Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-05 00:16 +0000
      Re: What Thinkest Thou Of LO Donate Banner? John Ames <commodorejohn@gmail.com> - 2025-12-03 14:41 -0800
        Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-04 03:05 +0000
      Re: What Thinkest Thou Of LO Donate Banner? vallor <vallor@vallor.earth> - 2025-12-07 04:01 +0000
        Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-08 02:32 +0000
          Re: What Thinkest Thou Of LO Donate Banner? vallor <vallor@vallor.earth> - 2025-12-08 04:36 +0000
            Re: What Thinkest Thou Of LO Donate Banner? vallor <vallor@vallor.earth> - 2025-12-08 14:30 +0000
              Re: What Thinkest Thou Of LO Donate Banner? pothead <pothead@snakebite.com> - 2025-12-08 23:21 +0000
                Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-09 10:01 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-10 01:37 +0000
                Re: What Thinkest Thou Of LO Donate Banner? pothead <pothead@snakebite.com> - 2025-12-10 18:13 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Brock McNuggets <brock.mcnuggets@gmail.com> - 2025-12-10 20:06 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-12 07:44 +0000
                Re: What Thinkest Thou Of LO Donate Banner? Daniel70 <daniel47@nomail.afraid.org> - 2025-12-12 22:39 +1100
                Re: What Thinkest Thou Of LO Donate Banner? The Natural Philosopher <tnp@invalid.invalid> - 2025-12-12 12:18 +0000
              SYSCALL "Carlos E.R." <robin_listas@es.invalid> - 2025-12-10 14:01 +0100
            Re: What Thinkest Thou Of LO Donate Banner? Gremlin <nobody@haph.org> - 2025-12-10 01:37 +0000

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