In -X FILEHANDLE, how to derive the -C of all files in a $dir variable?

taint has asked for the wisdom of the Perl Monks concerning the following question:

Greetings everyone,
I've been struggling with an attempt to clobber symlinks in a folder, if they are older than N minutes.
After much work with File::Find, I found that I am unable to make it work. SO, I decided to look to perlfunc's -X (-C in this case). which will return the Creation-time, which I can compare to Current-time. Allowing me to clobber anything older than 11 minutes from now.
Problem is, I'm not smart enough to figure out to how list the files Creation-time with perlfunc's -C. Looking at How do I delete... get's me close. But does mtime (modified) == ctime?
I could get close:

# delete $file if it's not been modified for 15 minutes
if ( (stat $file)[9] < time() - (3600 / 5) ) {
    unlink $file;
}
[download]

Never mind the example above, it doesn't work, it returns:

Use of uninitialized value in numeric lt (<) at line 12 (#1)
 (W uninitialized) An undefined value was used as if it were already
 defined. It was interpreted as a "" or a 0, but maybe it was a mistak
+e.
 To suppress this warning assign a defined value to your variables.
[download]

Would anyone be willing to provide an example, please?

Thank you for all your consideration

--chris

#!/usr/bin/perl -Tw
use perl::always;
my $perl_version = "5.12.4";
print $perl_version;

Comment on In -X FILEHANDLE, how to derive the -C of all files in a $dir variable? Select or Download Code

Replies are listed 'Best First'.
Re: In -X FILEHANDLE, how to derive the -C of all files in a $dir variable? by kcott (Archbishop) on Apr 27, 2013 at 06:18 UTC
G'day Chris, The reason that your stat version failed was probably due to `$file` not existing (possibly deleted in an earlier test). The code is fine; although, I would question your use of parentheses — see the operator precedence table in perlop. Also, note that 15mins. is 900secs. but `3600 / 5 == 720` (i.e. 12 mins.): `60 * 15` would be a clearer indication of the value you want. I'd recommend that you run some tests (similar to what I show below) which simply indicate what files are to be deleted. When you're happy everything works, then start using unlink. A backup of the directory you're working in would also be a good idea. $ perl -Mstrict -Mwarnings -E ' my $file = q{pm_1030903.dummy}; say "(stat \$file)[9] = ", (stat $file)[9]; say "15 mins. ago = ", time - 60 * 15; if ( (stat $file)[9] < time - 60 * 15 ) { say "[stat] Will delete $file"; } say "-C \$file = ", -C $file; say "15 mins. in days = ", 6015 / (246060); if ((-C $file) > 6015 / (246060)) { say "[-C] Will delete $file"; } ' (stat $file)[9] = 1367039733 15 mins. ago = 1367041074 [stat] Will delete pm_1030903.dummy -C $file = 0.0151736111111111 15 mins. in days = 0.0104166666666667 [-C] Will delete pm_1030903.dummy [download] -- Ken	[reply] [d/l] [select]
Re: In -X FILEHANDLE, how to derive the -C of all files in a $dir variable? by BrowserUk (Patriarch) on Apr 27, 2013 at 04:42 UTC
From perlfunc: -M Script start time minus file modification time, in days.* -A Same for access time. -C Same for inode change time* So, for 15 minutes you want any matching file where the return from -C is > than 1560 / 86400: `while( glob '' ) { if( -C() > 0.010416 ) { unlink $_; } }` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]