Needed a quick way to see if my server distro that I setup years ago was running 32bit or not, since with time I had forgotten. Note: does not check _hardware_ e.g. /proc/cpuinfo but rather the kernel installed Show Sample Output

This command tell you if your hardware is 32 or 64 bits even if you install a 32bits OS on a 64 bits hardware. If your distro don't support the -q switch, try doing : grep &>/dev/null '\<lm\>' /proc/cpuinfo && echo 64 bits || echo 32 bits

This is likely only valid on Solaris based systems. Unfortunately a lot of the more universal techniques for determining if a system is 32bit or 64bit on x86 solaris fail to give much more information than "i86pc" Show Sample Output

CPU flags: rm --> 16-bit processor (real mode) tm --> 32-bit processor (? mode) lm --> 64-bit processor (long mode)

Let's you examine, for example, whether infrastructure folks really provisioned the correct setup. Java 64-bit checklist 1. check if hardware is 64-bit capable by looking for lm flag grep -l 'flags.*\<lm\>' /proc/cpuinfo 2. check if kernel is 64-bit getconf LONG_BIT | grep '64' 3. check if java is 64-bit (simply look for 64-bit in output - if present, then it is, if absent, then it is 32-bit) java -version Show Sample Output

Avoids cat abuse ;)

Display the machine "hardware name" 32 or 64 bit. "x86_64" is shown on 64 bit machines "i686" is typically shown on 32 bit machines (although, you might also see "i386" or "i586" on older Linuxen). On other "unix-like" systems, other hardware names will be displayed. For example, on AIX, "uname -m" gives the "machine sequence number". For whatever reason, IBM decided that "uname -M" would give the machine type and model. (ref: http://www.ibm.com/developerworks/aix/library/au-aix-systemid.html ) On Sun Solaris, "uname -m" can be used to determine the chip type and "isainfo -v" will reveal if the kernel is 64 or 32 bit. (ref: http://www.ibiblio.org/pub/packages/solaris/sparc/html/32.and.64.bit.packages.html ) A more reliable way to determine "64-bit ness" across different Unix type systems is to compile the following simple C program: cat <<eeooff > bits.c /* * program bits.c * purpose Display "32" or "64" according to machine type * written January 2013 * reference http://www.unix.org/whitepapers/64bit.html */ /* hmm, curious that angle-brackets removed by commandlinefu.com data input processing? */ #include "/usr/include/stdio.h" long lv = 0xFFFFFFFF; main ( ) { printf("%2d\n",(lv < 0)?32:64); } eeooff Compile and run thusly: cc -o bits bits.c; ./bits Show Sample Output

CPU flags: rm --> 16-bit processor (real mode) tm --> 32-bit processor (? mode) lm --> 64-bit processor (long mode)