Shams wrote: > > Hi, > > Thanks for the info. > > Yes I have a 64-bit cpu but technically why is this needed, can it be just > solved > with having all the 64-bit libs in /usr/lib? > > Does this mean that if I have a 64-bit cpu that is not capable of supporting > ia32 > then only /usr/lib will exist? > > Thanks > Shams > > -- > > "Steve Siegfried" <sos@xxxxxxxx> wrote in message > news:200706080120.l581KWEl010638@xxxxxxxxxxxxxxxx > > Shams wrote: > >> > >> Hi, > >> > >> I noticed that Fedora has both /usr/lib and /usr/lib64 > >> > >> Is this only on Fedora or standard across many Linux distros? > >> Why is this needed, I mean why not just have /usr/lib? > >> > >> Thanks > >> Shams > >> > > > > Umm... because you've got a 64-bit CPU that supports both ia32 and > > either ia64 or x86-64? > > > > This is pretty standard across most 64-bit capable distributions. With the /usr/lib64 stuff, you can build/install 64 bit binaries and expect them to run. With the /usr/lib stuff, you can build/install 32 bit binaries and expect them to run, too. So basically, you have a CPU that can run either flavor of binary; thus the two flavors of libraries to support that. Is there any real advantage to using either 32 bit or 64 bit binaries on a 64 bit CPU? For most programs, not really, mostly since very few folks have anywhere near 32 bits worth (let alone more) of real memory. Yeah... you can write larger programs with 64 bit binaries, but without the real memory to run 'em in, most large programs (even 32 bit ones) grow right up to the point were they exceed available memory, start swapping and then sloooow waaaaaaaaaaay dowwwwwwwwnnnnnnnnnnnnnnnnnn. And yes, if you had a 64 bit CPU that didn't support a 32 bit mode, then you'd probably only have /usr/lib. However, there aren't that many pure 64 bit chips out there (leastways that most folks can afford). -S
