File::stat - by-name interface to Perl's built-in stat() functions
use File::stat;
my $st = stat($file) or die "No $file: $!";
if ( ($st->mode & 0111) && ($st->nlink > 1) ) {
print "$file is executable with lotsa links\n";
}
if ( -x $st ) {
print "$file is executable\n";
}
use Fcntl "S_IRUSR";
if ( $st->cando(S_IRUSR, 1) ) {
print "My effective uid can read $file\n";
}
use File::stat qw(:FIELDS);
stat($file) or die "No $file: $!";
if ( ($st_mode & 0111) && ($st_nlink > 1) ) {
print "$file is executable with lotsa links\n";
}
This module's default exports override the core stat() and lstat() functions, replacing them with versions that return "File::stat" objects. This object has methods that return the similarly named structure field name from the stat(2) function; namely, dev, ino, mode, nlink, uid, gid, rdev, size, atime, mtime, ctime, blksize, and blocks.
As of version 1.02 (provided with perl 5.12) the object provides "-X"
overloading, so you can call filetest operators (-f
, -x
, and so on) on it. It also provides a ->cando
method, called like
$st->cando( ACCESS, EFFECTIVE )
where ACCESS is one of S_IRUSR
, S_IWUSR
or S_IXUSR
from the Fcntl module, and EFFECTIVE indicates whether to use effective (true) or real (false) ids. The method interprets the mode
, uid
and gid
fields, and returns whether or not the current process would be allowed the specified access.
If you don't want to use the objects, you may import the ->cando
method into your namespace as a regular function called stat_cando
. This takes an arrayref containing the return values of stat
or lstat
as its first argument, and interprets it for you.
You may also import all the structure fields directly into your namespace as regular variables using the :FIELDS import tag. (Note that this still overrides your stat() and lstat() functions.) Access these fields as variables named with a preceding st_
in front their method names. Thus, $stat_obj->dev()
corresponds to $st_dev if you import the fields.
To access this functionality without the core overrides, pass the use
an empty import list, and then access functions with their full qualified names:
use File::stat ();
my $st = File::stat::stat($file);
On the other hand, the built-ins are still available via the CORE::
pseudo-package even if you let File::stat override them:
use File::stat;
my ($dev, $ino, $mode) = CORE::stat($file);
As of version 1.15 (provided with perl 5.44) stat
and lstat
can be called without arguments, in which case $_
is used (just like the built-in stat
/lstat
functions):
my $st_1 = stat; # stat($_)
my $st_2 = lstat; # lstat($_)
The built-in stat
and lstat
functions recognize the special filehandle _
(underscore) to indicate that no actual stat
be done; instead the results of the last stat
or lstat
or filetest operation should be returned. This syntax does not work with File::stat, but the same result can be achieved by passing stat
a reference to the *_
typeglob:
use File::stat;
my $stat_obj = stat \*_; # reuse results of last stat operation
Alternatively, another workaround is to explicitly populate the object using the unexported and undocumented populate() function with CORE::stat():
my $stat_obj = File::stat::populate(CORE::stat(_));
The filetest operators -t
, -T
and -B
are not implemented, as they require more information than just a stat buffer.
These can all be disabled with
no warnings "File::stat";
You have tried to use one of the -rwxRWX
filetests with use filetest 'access'
in effect. File::stat
will ignore the pragma, and just use the information in the mode
member as usual.
VMS systems have a permissions structure that cannot be completely represented in a stat buffer, and unlike on other systems the builtin filetest operators respect this. The File::stat
overloads, however, do not, since the information required is not available.
While this class is currently implemented using the Class::Struct module to build a struct-like class, you shouldn't rely upon this.
Tom Christiansen