octal 0666 is equivalent to decimal 438.

octal 0777 is equivalent to decimal 511.

When you call fn(0666) , perl interprets 0666 as a number, and stores it as the integer value in the function @_ array. If you print $_[0]; then you will see the integer value in the default decimal representation; if you want to see the number as an octal, format it, like with printf "%#o", $_[0];

If you pass this value to a chmod using chmod(0666) or chmod($_[0]) then it will be properly interpreted as the right mode.

If you want to pass it as a string instead (your q(0666) example), then you can extract the underlying value (as shown in the chmod documentation) as chmod(oct(q(0666))) or chmod(oct($_[0])) .

In reply to Re: octal number mysteriously changes after pass to subroutine by pryrt
in thread octal number mysteriously changes after pass to subroutine by Anonymous Monk

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