Beefy Boxes and Bandwidth Generously Provided by pair Networks
more useful options
 
PerlMonks  

Re: $ENV {'FOO'} $foo

by wog (Curate)
on Feb 14, 2002 at 23:57 UTC ( #145586=note: print w/replies, xml ) Need Help??


in reply to $ENV {'FOO'} $foo

On most systems there will be a signifigant performance overhead from using %ENV rather then a "normal" variable. %ENV access a system dependent table, which is typically not designed for efficient access. (On UNIX, for example, the environment table is (usually, at least) stored as an unordered, C-style, null-terminated array of strings in the format "KEY=VALUE". Searching through this to find an element is not very efficient, obviously.) Unless you need to interface with C code that uses environment variables or want to pass things to your child processes or recieve things from parent processes, you probably shouldn't use %ENV.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://145586]
help
Chatterbox?
[stevieb]: 16.96 hours of runtime of a Raspberry Pi on a 12v, 7.2Ah battery :) Now to watch now long it takes to recharge the battery completely with my 18v solar cells in the sun :)
[stevieb]: my high-range estimate was 18 hours
[stevieb]: battery was at about 95% capacity when the test began
[stevieb]: in the meantime while it was on battery, I got my shift register issues fixed, as well as certain interrupt issues

How do I use this? | Other CB clients
Other Users?
Others meditating upon the Monastery: (6)
As of 2017-03-26 15:23 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    Should Pluto Get Its Planethood Back?



    Results (315 votes). Check out past polls.