System Administration Guide: Advanced Administration

ProcedureHow to Determine Whether a System Has 32–Bit or 64–Bit Capabilities Enabled

  1. Use the isainfo command to determine whether a system has 32–bit or 64-bit capabilities enabled.


    # isainfo options
    

    The isainfo command, run without specifying any options, displays the name or names of the native instruction sets for applications supported by the current OS version.

    -v

    Prints detailed information about the other options.

    -b

    Prints the number of bits in the address space of the native instruction set.

    -n

    Prints the name of the native instruction set used by portable applications supported by the current version of the OS.

    -k

    Prints the name of the instruction set or sets that are used by the OS kernel components such as device drivers and STREAMS modules.


    Note –

    For x86 based systems, the isalist command can also be used to display this information.

    For more information, see the isalist(1) man page.



Example 5–1 SPARC: Determining Whether a System Has 32–Bit or 64–Bit Capabilities Enabled

The isainfo command output for an UltraSPARC system that is running previous releases of the Oracle Solaris OS using a 32-bit kernel is displayed as follows:


$ isainfo -v
32-bit sparc applications

This output means that this system can support only 32–bit applications.

The current release of the Oracle Solaris OS only ships a 64–bit kernel on SPARC based systems. The isainfo command output for an UltraSPARC system that is running a 64–bit kernel is displayed as follows:


$ isainfo -v
64-bit sparcv9 applications 
32-bit sparc applications

This output means that this system is capable of supporting both 32–bit and 64–bit applications.

Use the isainfo -b command to display the number of bits supported by native applications on the running system.

The output from a SPARC based, x86 based, or UltraSPARC system that is running the 32–bit Oracle Solaris OS is displayed as follows:


$ isainfo -b
32

The isainfo command output from a 64–bit UltraSPARC system that is running the 64–bit Oracle Solaris OS is displayed as follows:


$ isainfo -b
64

The command returns 64 only. Even though a 64–bit UltraSPARC system can run both types of applications, 64–bit applications are the best kind of applications to run on a 64–bit system.



Example 5–2 x86: Determining Whether a System Has 32–Bit or 64–Bit Capabilities Enabled

The isainfo command output for an x86 based system that is running the 64-bit kernel is displayed as follows:


$ isainfo
amd64 i386

This output means that this system can support 64–bit applications.

Use the isainfo -v command to determine if an x86 based system is capable of running a 32–bit kernel.


$ isainfo -v
64-bit amd64 applications
        fpu tsc cx8 cmov mmx ammx a3dnow a3dnowx fxsr sse sse2 
32-bit i386 applications
        fpu tsc cx8 cmov mmx ammx a3dnow a3dnowx fxsr sse sse2 

This output means that this system can support both 64–bit and 32–bit applications.

Use the isainfo -b command to display the number of bits supported by native applications on the running system.

The output from an x86 based system that is running the 32–bit Oracle Solaris OS is displayed as follows:


$ isainfo -b
32

The isainfo command output from an x86 based system that is running the 64–bit Oracle Solaris OS is displayed as follows:


$ isainfo -b
64

You can also use the isalist command to determine whether an x86 based system is running in 32–bit or 64–bit mode.


$ isalist
amd64 pentium_pro+mmx pentium_pro pentium+mmx pentium i486 i386 i86

In the preceding example, amd64 indicates that the system has 64–bit capabilities enabled.