SETARCH(8)                   System Administration                  SETARCH(8)

       setarch  -  change  reported  architecture  in  new program environment
       and/or set personality flags

       setarch [arch] [options] [program [argument...]]

       setarch --list|-h|-V

       arch [options] [program [argument...]]

       setarch modifies execution domains and process personality flags.

       The execution domains currently only affects the output  of  uname  -m.
       For  example,  on  an  AMD64  system, running setarch i386 program will
       cause program to see i686 instead of x86_64 as the  machine  type.   It
       also allows to set various personality options.  The default program is

       Since version 2.33 the arch  command  line  argument  is  optional  and
       setarch   may  be  used  to  change  personality  flags  (ADDR_LIMIT_*,
       SHORT_INODE, etc) without modification of the execution domain.

       --list List  the  architectures  that  setarch  knows  about.   Whether
              setarch  can actually set each of these architectures depends on
              the running kernel.

              Causes the program to see a kernel version number beginning with
              2.6.  Turns on UNAME26.

       -v, --verbose
              Be verbose.

       -3, --3gb
              Specifies  program should use a maximum of 3GB of address space.
              Supported on x86.  Turns on ADDR_LIMIT_3GB.

       --4gb  This option has no effect.  It is retained for backward compati-
              bility only, and may be removed in future releases.

       -B, --32bit
              Limit  the  address  space to 32 bits to emulate hardware.  Sup-
              ported on ARM and Alpha.  Turns on ADDR_LIMIT_32BIT.

       -F, --fdpic-funcptrs
              Treat user-space function pointers to signal handlers as  point-
              ers to address descriptors.  This option has no effect on archi-
              tectures that do not support  FDPIC  ELF  binaries.   In  kernel
              v4.14 support is limited to ARM, Blackfin, Fujitsu FR-V, and Su-
              perH CPU architectures.

       -I, --short-inode
              Obsolete bug emulation flag.  Turns on SHORT_INODE.

       -L, --addr-compat-layout
              Provide legacy virtual address space layout.  Use when the  pro-
              gram  binary  does  not  have PT_GNU_STACK ELF header.  Turns on

       -R, --addr-no-randomize
              Disables randomization of the virtual address space.   Turns  on

       -S, --whole-seconds
              Obsolete bug emulation flag.  Turns on WHOLE_SECONDS.

       -T, --sticky-timeouts
              This makes select(2), pselect(2), and ppoll(2) system calls pre-
              serve the timeout value instead of modifying it to  reflect  the
              amount  of  time not slept when interrupted by a signal handler.
              Use when program depends on this behavior.  For more details see
              the  timeout  description  in  select(2)  manual page.  Turns on

       -X, --read-implies-exec
              If this  is  set  then  mmap(3)  PROT_READ  will  also  add  the
              PROT_EXEC bit - as expected by legacy x86 binaries.  Notice that
              the ELF loader will automatically set this bit when  it  encoun-
              ters a legacy binary.  Turns on READ_IMPLIES_EXEC.

       -Z, --mmap-page-zero
              SVr4 bug emulation that will set mmap(3) page zero as read-only.
              Use when program depends on this behavior, and the  source  code
              is not available to be fixed.  Turns on MMAP_PAGE_ZERO.

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

       setarch --addr-no-randomize mytestprog
       setarch ppc32 rpmbuild --target=ppc --rebuild foo.src.rpm
       setarch ppc32 -v -vL3 rpmbuild --target=ppc --rebuild bar.src.rpm
       setarch ppc32 --32bit rpmbuild --target=ppc --rebuild foo.src.rpm

       Elliot Lee <>
       Jindrich Novy <>
       Karel Zak <>

       personality(2), select(2)

       The  setarch command is part of the util-linux package and is available
       from Linux Kernel Archive <

util-linux                       December 2017                      SETARCH(8)

Man(1) output converted with man2html
list of all man pages