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A comment on The low-down on LOADALL (1990).

Re:The low-down on LOADALL (1990) by FartyMcFarter on Tuesday January 19, 2021 @02:24PM (#25837615)
Piece of trivia:

> ** 0F 05 hex **

Nowadays this opcode is used for the "syscall" instruction.

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Re:The low-down on LOADALL (1990) by rahimiali on Tuesday January 19, 2021 @02:54PM (#25837999)
isn't 0x80 the syscall opcode on x86?
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Re:The low-down on LOADALL (1990) by FartyMcFarter on Tuesday January 19, 2021 @03:00PM (#25838072)
You might be thinking of "int 0x80" which gets assembled to 0xCD 0x80.

According to this stackoverflow answer, "int 0x80" is a Linux-specific legacy way to do syscalls:

https://stackoverflow.com/questions/12806584/what-is-better-...

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Re:The low-down on LOADALL (1990) by toast0 on Tuesday January 19, 2021 @03:30PM (#25838485)
int 0x80 is legacy, and x86, but it isn't specific to Linux.

FreeBSD (and AFAIK other BSDs) also use(d) it; most likely any Unix system on x86 that doesn't require a processor with sysenter/syscall instructions would use int 0x80 to do syscalls.

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Re:The low-down on LOADALL (1990) by rahimiali on Tuesday January 19, 2021 @03:17PM (#25838316)
that's indeed my confusion. thank you for explaining.
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