Determine whether a CPU has 64 bit capability or not

if cat /proc/cpuinfo | grep " lm " &> /dev/null; then echo "Got 64bit" ; fi
Check if you have 64bit by looking for "lm" in cpuinfo. lm stands for "long mem". This can also be used without being root.

4
By: xeor
2010-04-10 15:31:58

1 Alternatives + Submit Alt

What Others Think

This is a bit cleaner and simpler: grep -q " lm " /proc/cpuinfo && echo "Got 64bit"
eightmillion · 488 weeks and 2 days ago
Just a nitpick: "lm" stands for long mode (not long mem), meaning that the processor registers are 64bit long in this mode. By the way, /proc/cpuinfo works on Linux only, of course, so this is not portable (except that it also works on FreeBSD when the "Linuxulator" is enabled and linprocfs mounted on /compat/linux/proc). On Solaris use this command to find out if 64bit is supported by the platform: isainfo -bv On FreeBSD, this command can be be used: grep -w "LM" /var/run/dmesg.boot && echo "Got 64bit"
inof · 488 weeks and 2 days ago
My two cents, for Red Hat flavours: arch sample output: x86_64
KoRoVaMiLK · 488 weeks ago

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