perl -V (note upper case V) displays a lot of useful data, which you can report on individually...

• perl -V:archname will tell you if it's a 32 or 64bit perl program.
• perl -V:ivsize if this outputs 8 perl can use 64bit integers, if 4 32bit.
• perl -V:ptrsize if this outputs 4 your perl uses 32bit pointers, if 8 64bit.

To use perlbrew to install a 64bit perl do perlbrew --64all install perlversionhere.

It depends on what you mean by "32 or 64 version".

If you want to check if it uses 32-bit integers or 64-bit integers, use the following:

perl -V:ivsize      # use Config; say $Config{ivsize}
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• If the returned value is 4, your Perl uses 32-bit integers.
• If the returned value is 8, your Perl uses 64-bit integers.

If you want to check if it uses 32-bit pointers or 64-bit pointers, use the following:

perl -V:ptrsize     # use Config; say $Config{ptrsize}
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• If the returned value is 4, your Perl can address 4 GB of RAM.
• If the returned value is 8, your Perl can address "unlimited" RAM.

If you want to check if it's a 32-bit program or a 64-bit program, use the following:

perl -V:archname    # use Config; say $Config{archname}
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• If the returned value includes x86_64, it's a 64-bit process.
• If the returned value includes x86 (but not x86_64), it's a 32-bit process.

This value is also included in the output of perl -v.

Note: You shouldn't be checking use64bitint or use64bitall as these indicate what parameters were passed to Configure rather than provide information about what was actually used.

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