SEGBRK(2) SEGBRK(2)
NAME
segbrk - change memory allocation
SYNOPSIS
#include <u.h>
#include <libc.h>
void* segbrk(void *saddr, void *addr)
DESCRIPTION
Segbrk sets the system's idea of the lowest unused location
of a segment to addr rounded up to the next multiple of a
page size, typically 4096 bytes. The segment is identified
by saddr which may be any valid address within the segment.
A call to segbrk with a zero addr argument returns the
address of the top of bss.
The system will prevent segments from overlapping and will
not allow the length of the text, data, or stack segment to
be altered.
SOURCE
/sys/src/libc/9syscall
SEE ALSO
brk(2), segattach(2), segflush(2)
/proc/*/segment
DIAGNOSTICS
Sets errstr. Segbrk returns (void*)-1 on error.
BUGS
Segbrk is not fully defined or implemented. In particular,
it cannot always return the top of bss when called with a
zero addr argument. The segbrk system call may go away or
be re-implemented to give more general segment control, sub-
suming the functions of brk(2), segflush(2) and segfree in
segattach(2).
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