36 lines
912 B
C
36 lines
912 B
C
#include <sys/cdefs.h>
|
|
#include "namespace.h"
|
|
#include <lib.h>
|
|
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#ifdef __weak_alias
|
|
__weak_alias(brk, _brk)
|
|
#endif
|
|
|
|
extern char *_brksize;
|
|
|
|
/* Both OSF/1 and SYSVR4 man pages specify that brk(2) returns int.
|
|
* However, BSD4.3 specifies that brk() returns char*. POSIX omits
|
|
* brk() on the grounds that it imposes a memory model on an architecture.
|
|
* On the other hand, they are so crucial to correct operation of so many
|
|
* parts of the system, that we have chosen to hide the name brk using _brk,
|
|
* as with system calls. In this way, if a user inadvertently defines a
|
|
* procedure brk, MINIX may continue to work because the true call is _brk.
|
|
*/
|
|
int brk(addr)
|
|
void *addr;
|
|
{
|
|
message m;
|
|
|
|
if (addr != _brksize) {
|
|
memset(&m, 0, sizeof(m));
|
|
m.m_lc_vm_brk.addr = addr;
|
|
if (_syscall(VM_PROC_NR, VM_BRK, &m) < 0) return(-1);
|
|
_brksize = addr;
|
|
}
|
|
return(0);
|
|
}
|
|
|