do not allow brk() below _end
[unix-history] / usr / src / lib / libc / vax / sys / sbrk.s
/* sbrk.s 4.2 83/07/26 */
#include "SYS.h"
#define SYS_brk 17
.globl _end
.globl minbrk
.globl curbrk
.data
minbrk: .long _end
curbrk: .long _end
.text
ENTRY(sbrk)
addl3 curbrk,4(ap),-(sp)
pushl $1
movl ap,r3
movl sp,ap
chmk $SYS_brk
jcs err
movl curbrk,r0
addl2 4(r3),curbrk
ret
err:
jmp cerror