.TH "sbrk()" "" "" "General Function (libc)"
.PC "Increase a program's data space"
.B "#include <unistd.h>"
\fBchar *sbrk(\fIincrement\^\fB) unsigned int \fIincrement\^\fB;\fR
.PP
.B sbrk()
increases a program's data space by
.I increment
bytes.
.B malloc()
calls
.B sbrk()
should you attempt to allocate more space than is available in the
program's data space.
.PP
If all goes well,
.B sbrk()
returns the old break value.
Otherwise, if an error occurs,
.BR sbrk()
returns \-1 and sets
.B errno
to an appropriate value.
.SH "See Also"
.Xr "brk()," brk
.Xr "libc," libc
.Xr "malloc()" malloc
.SH Notes
.B sbrk()
will not increase the size of the program data area if the
physical memory requested exceeds the physical memory allocated by \*(CO.
.B sbrk()
does not keep track of how space is used; therefore, memory seized with
.B sbrk()
cannot be freed.
.IR "Caveat utilitor" .
