Re^3: Detecting if a program or file exists

What about if I want to make sure a module (Win32::DirSize) is installed?

# see perldoc -f require for more info
my $class = 'Win32::DirSize';
eval "require $class" or die "Couldn't load $class: $@";
[download]

And what about another program that only has one executable file?

my $binary = "/path/to/executable";
-x $binary or die "$binary not found";
[download]

Comment on Re^3: Detecting if a program or file exists Select or Download Code

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Re^4: Detecting if a program or file exists by blazar (Canon) on Oct 18, 2005 at 07:06 UTC
And what about another program that only has one executable file? `my $binary = "/path/to/executable"; -x $binary or die "$binary not found";` [download] FM seems to be under Windows, since he asks about Win32::DirSize. But I guess `-x` is *NIX-centric and I don't know how it would behave under redmondish environments. Maybe it would just evaporate silently to `-f`, but I would probably use directly the latter: -f or die "`$_' binary not found\n" for 'C:/path/to/executable'; [download]	[reply] [d/l] [select]
Re^4: Detecting if a program or file exists by ChrisS (Monk) on Oct 18, 2005 at 13:38 UTC
You might be able to determine if a module is installed without explicitly requiring or using it by using a technique I described in Re: Case Insensitivity on Windows.	[reply]
Re^4: Detecting if a program or file exists by FM (Acolyte) on Oct 18, 2005 at 18:01 UTC
Thanks a bunch. It worked as expected, however, the -x did not work and I finally use -e. How is this going to affect what I am trying to do? Thanks, FM	[reply]
Re^5: Detecting if a program or file exists by Limbic~Region (Chancellor) on Oct 18, 2005 at 18:24 UTC
FM, Take a look at perldoc -f -X. The difference between -e (exists) and -x (executable by effective UID/GID) may be a big one. Before I go any further - what do you mean -x didn't work? What happens when you try to run it? What's the output? What's the error message? Saying "it doesn't work" isn't very helpful. Cheers - L~R	[reply]


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