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[unix-history] / usr / source / s5 / sbrk.s

/old = sbrk(increment);
/
/sbrk gets increment more core, and returns a pointer
/       to the beginning of the new core area
/
.globl  _sbrk,_end, cerror

_sbrk:
       mov     r5,-(sp)
       mov     sp,r5
       mov     nd,0f
       add     4(r5),0f
       sys     0; 9f
       bec     1f
       jmp     cerror
1:
       mov     nd,r0
       add     4(r5),nd
       mov     (sp)+,r5
       rts     pc

.globl  _brk
/ brk(value)
/ as described in man2.
/ returns 0 for ok, -1 for error.

_brk:
       mov     r5,-(sp)
       mov     sp,r5
       mov     4(r5),0f
       sys     0; 9f
       bec     1f
       jmp     cerror
1:
       mov     4(r5),nd
       clr     r0
       mov     (sp)+,r5
       rts     pc

.data
9:
       sys     break; 0:..
nd:     _end