brk, sbrk, break \- change core allocation
sets the system's idea of the lowest location not used by the program
(rounded up to the next multiple of 64 bytes
on the PDP11, 256 bytes on the Interdata 8/32,
and 512 bytes on a VAX-11).
and below the stack pointer
are not in the address space and will thus
cause a memory violation if accessed.
In the alternate function
more bytes are added to the
program's data space and a pointer to the
start of the new area is returned.
When a program begins execution via
highest location defined by the program
Ordinarily, therefore, only programs with growing
Zero is returned if the break could be set;
\-1 if the program requests more
memory than the system limit
or if too many segmentation
registers would be required to implement the break.
Setting the break in the range
0177701 to 0177777 (on the PDP11) is the same as setting it to zero.
The name of the routine differs from that in C