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Why isn't my octal data interpreted correctly?

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Why isn't my octal data interpreted correctly?

Perl only understands octal and hex numbers as such when they occur as literals in your program. If they are read in from somewhere and assigned, no automatic conversion takes place. You must explicitly use oct() or hex() if you want the values converted. oct() interprets both hex (``0x350'') numbers and octal ones (``0350'' or even without the leading ``0'', like ``377''), while hex() only converts hexadecimal ones, with or without a leading ``0x'', like ``0x255'', ``3A'', ``ff'', or ``deadbeef''.

This problem shows up most often when people try using chmod(), mkdir(), umask(), or sysopen(), which all want permissions in octal.

    chmod(644,  $file); # WRONG -- perl -w catches this
    chmod(0644, $file); # right

Source: Perl FAQ: Data Manipulation
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.
Next: Does perl have a round function? What about ceil() and floor()?

Previous: Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)?

(Corrections, notes, and links courtesy of RocketAware.com)

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