PR_SET_MM_START_BRK(2const) — Linux manual page

PR_SET_MM_START_BRK(2const)                   PR_SET_MM_START_BRK(2const)

NAME         top

       PR_SET_MM_START_BRK - modify kernel memory map descriptor fields

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <linux/prctl.h>  /* Definition of PR_* constants */
       #include <sys/prctl.h>

       int prctl(PR_SET_MM, PR_SET_MM_START_BRK, unsigned long addr, 0L, 0L);

DESCRIPTION         top

       Set the address above which the program heap can be expanded with
       brk(2) call.

       The address must be greater than the ending address of the current
       program data segment.  In addition, the combined size of the
       resulting heap and the data segment can't exceed the RLIMIT_DATA
       resource limit (see setrlimit(2)).

RETURN VALUE         top

       On success, 0 is returned.  On error, -1 is returned, and errno is
       set to indicate the error.

ERRORS         top

       EINVAL addr is greater than TASK_SIZE (the limit on the size of
              the user address space for this architecture).

       EINVAL addr is less than or equal to the end of the data segment
              or specifies a value that would cause the RLIMIT_DATA
              resource limit to be exceeded.

STANDARDS         top

       Linux.

HISTORY         top

       Linux 3.3.

SEE ALSO         top

       prctl(2), PR_SET_MM(2const)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17    PR_SET_MM_START_BRK(2const)

Pages that refer to this page: PR_SET_MM(2const),  PR_SET_MM_BRK(2const),  PR_SET_MM_MAP(2const)

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