Beefy Boxes and Bandwidth Generously Provided by pair Networks
Clear questions and runnable code
get the best and fastest answer
 
PerlMonks  

Re^3: greater efficiency required (ls, glob, or readdir?)

by JavaFan (Canon)
on Aug 27, 2008 at 19:37 UTC ( #707275=note: print w/replies, xml ) Need Help??


in reply to Re^2: greater efficiency required (ls, glob, or readdir?)
in thread greater efficiency required (ls, glob, or readdir?)

Actually, $dir and $_ will only be interpreted by the shell if they contain "funny" characters. If a string passed as argument to qx or one-arg system contains just alphanums, underscores and whitespace, no shell gets involved, perl will call execv directly.

But obviously, if you don't know what $dir contains, you shouldn't use `ls $dir`, and if you aren't in control of the content of the directory you should use `cat $_`.

Even if you don't think that this is important in your case, it's better to make the code more maintainable and re-usable for security-aware scenarios.

I cannot agree with that, if only for the reasons it's often not mutually possible. More maintable code usually means simpler code, while code that needs to be run in a possible hostile environment tends to be more complex than code that doesn't have to run in such an environment. "More maintable" and "re-usable for security aware scenarios" are most of the time conflicting requirements.

  • Comment on Re^3: greater efficiency required (ls, glob, or readdir?)

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://707275]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others about the Monastery: (5)
As of 2020-11-28 11:37 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found

    Notices?