NAME

     brk, sbrk - change data segment size

SYNOPSIS

     #include <unistd.h>

     int brk(void *end_data_segment));

     void *sbrk(ptrdiff_t increment));

DESCRIPTION

     brk sets the end of the data segment to the value  specified
     by  end_data_segment.   end_datasegment must be greater than
     end of the text segment and it must be 16kB before  the  end
     of the stack.

     sbrk increments the program's data space by increment bytes.
     sbrk isn't a system call, it is just a C library wrapper.

RETURN VALUE

     On success, brk returns zero, and sbrk returns a pointer  to
     the  start  of  the new area.  On error, -1 is returned, and
     errno is set to ENOMEM.

CONFORMING TO

     BSD 4.3

     brk and sbrk are not defined in the C Standard and are deli-
     berately  excluded from the POSIX.1 standard (see paragraphs
     B.1.1.1.3 and B.8.3.3).

SEE ALSO

     execve(2), getrlimit(2), malloc(3)