我怎么知道我在Perl脚本中是在64位还是32位Linux上运行？

Question

I don't want to directly access the shell (for example to use uname). I am looking for a fast-forward way to detect the architecture (only if it is 32 or 64 bits), once I know I am on linux.

Answer 1

There are 3 separate questions you could be asking:

Note for all that there's not a single magic "64-bit", there's lots of different things that could mean.

1. What's the hardware? -- /proc/cpuinfo contains this info in a hard to parse manner. You basically need to have a table of what the different CPUs are. I believe you'll get numbers bigger than 32 in an "address sizes" if the kernel is 64-bit, though.
2. What's the OS/kernel? -- I believe use POSIX; and inspecting (POSIX::uname())[4] is the canonical answer, but -d /lib64 , -d /usr/lib64 being true is also a good indicator.
3. Is this a 64-bit perl? -- use Config; and look at $Config{archname} , $Config{myarchname} , $Config{use64bitint} , or some other variable in Config that matches up to what you believe "64 bit" means.

Answer 2

perl -e 'use Config; print $Config{longsize}';

Will return 8 bytes on a 64 bit implementation of Perl, and 4 bytes on a 32 bit implementation of Perl.

If you want to actually check the hardware, you'll have to either do a uname or check for something that only reasonably exists on a 64 bit machine (like /lib64). Note that it is often not very useful to know the hardware support for 64 bits if you are stuck in a 32 bit application.