ack/plat/msdos386/libsys/sys_isopen.s
David Given dc1f69be83 Most of read and write now works; filename-based operations partially work; but
there's a nasty memory corruption somewhere which needs investigating.
2022-08-19 00:08:57 +02:00

27 lines
351 B
ArmAsm

#
! $Source$
! $State$
! $Revision$
! Declare segments (the order is important).
.sect .text
.sect .rom
.sect .data
.sect .bss
.sect .text
! Say whether a given file descriptor number refers to a valid open file
! descriptor.
.define __sys_isopen
__sys_isopen:
mov ebx, esp
mov ebx, 4(bx)
mov eax, 0x4400
int 0x21
sbb eax, eax
inc eax
ret