uname26 (8) Linux Manual Page

setarch – change reported architecture in new program environment and set personality flags

Synopsis

setarch arch [options] [program [argument…]]

arch [options] [program [argument…]]

setarch –list|-h|-V

Description

setarch 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 /bin/sh.

Options

–list

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

–uname-2.6

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

-v, –verbose

Be verbose.

-3, –3gb

Specifies that processes should use a maximum of 3GB of address space on systems where it is supported (ADDR_LIMIT_3GB).

–4gb

Ignored (for backward compatibility only).

-B, –32bit

Turns on ADDR_LIMIT_32BIT.

-F, –fdpic-funcptrs

Userspace function pointers point to descriptors (turns on FDPIC_FUNCPTRS).

-I, –short-inode

Turns on SHORT_INODE.

-L, –addr-compat-layout

Changes the way virtual memory is allocated (turns on the ADDR_COMPAT_LAYOUT).

-R, –addr-no-randomize

Disables randomization of the virtual address space (turns on ADDR_NO_RANDOMIZE).

-S, –whole-seconds

Turns on WHOLE_SECONDS.

-T, –sticky-timeouts

Turns on STICKY_TIMEOUTS.

-X, –read-implies-exec

Turns on READ_IMPLIES_EXEC.

-Z, –mmap-page-zero

Turns on MMAP_PAGE_ZERO.

-V, –version

Display version information and exit.

-h, –help

Display help text and exit.

Examples

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

Author

Elliot Lee
Jindrich Novy

Availability

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